プロジェクトJSFでTomcat8を実行中にエラーが発生しましたか？

MavenとJSF2.2およびEclipseを使用したプロジェクトがあります。解決策を探して、何かを追加する提案を見つけました<dependencies>が、この依存関係がどれかわかりません。プロジェクトを実行しようとすると、例外がスローされます。

例外

java.lang.ClassNotFoundException: javax.faces.webapp.FacesServlet
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1324)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1177)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:550)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:531)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:150)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1105)
    at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1041)
    at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4932)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5218)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1396)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1386)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

pom.xml

    <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>br.com.ferpasys.webapp</groupId>
  <artifactId>ferpasys_webapp</artifactId>
  <packaging>war</packaging>
  <version>1.0</version>
  <name>FerpaSys Web Application</name>
  <description>ferpasys_web_app is a JSF project</description>


 <build>
    <!-- To define the plugin version in your parent POM -->
    <pluginManagement>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
    </plugins>

    </pluginManagement>    
  </build>



  <repositories>
    <repository>
        <id>prime-repo</id>
        <name>PrimeFaces Maven Repository</name>
        <url>http://repository.primefaces.org</url>
        <layout>default</layout>
    </repository>
</repositories>


  <dependencies>
    <dependency>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-war-plugin</artifactId>
        <version>2.4</version>
    </dependency>


        <dependency>
             <groupId>org.codehaus.groovy</groupId>
             <artifactId>groovy-all</artifactId>
             <version>2.3.0</version>
        </dependency>
        <!-- jasperreports -->
        <dependency>
                    <groupId>net.sf.jasperreports</groupId>
                    <artifactId>jasperreports</artifactId>
                    <version>5.6.0</version>
        </dependency>

        <!-- MySQL -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.29</version>
        </dependency>

        <!--h2 db-->
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <version>1.4.180</version>
        </dependency>


        <!-- eclipse link -->
        <dependency>
            <groupId>org.eclipse.persistence</groupId>
            <artifactId>eclipselink</artifactId>
            <version>2.5.0</version>
        </dependency>


        <!-- Hibernate Validator -->        
        <!-- JPA / Hibernate -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.6.4</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>4.1.6.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>4.1.6.Final</version>
        </dependency>

        <!-- Bean Validation / Hibernate -->
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>4.3.1.Final</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.16</version>
        </dependency>       
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>       
        <dependency>
            <groupId>javax.validation</groupId>
            <artifactId>validation-api</artifactId>
            <version>1.1.0.Final</version>
        </dependency>

        <!-- Apache Commons Email -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-email</artifactId>
            <version>1.3</version>
        </dependency>       
        <!-- JavaMail -->
        <dependency>
            <groupId>javax.mail</groupId>
            <artifactId>mail</artifactId>
            <version>1.4</version>
        </dependency>


    <!-- jsf -->
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-api</artifactId>
        <version>2.2.2</version>
    </dependency>
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-impl</artifactId>
        <version>2.2.2</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.0.1</version>
    </dependency>

    <!-- primefaces -->
    <dependency>
        <groupId>org.primefaces</groupId>
        <artifactId>primefaces</artifactId>
        <version>3.5</version>
    </dependency>
    <dependency>
        <groupId>org.primefaces.themes</groupId>
        <artifactId>bootstrap</artifactId>
        <version>1.0.9</version>    
    </dependency>

  </dependencies>

</project>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" version="3.0">
  <display-name>ferpasys_web_app</display-name>
  <servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>/faces/*</url-pattern>
  </servlet-mapping>
</web-app>

index.xhtml

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:ui="http://java.sun.com/jsf/facelets"
      xmlns:f="http://java.sun.com/jsf/core"
      xmlns:h="http://java.sun.com/jsf/html"> 

<h:head></h:head> 
<body> 
    Model:<h:inputText/>
</body> 
</html>

なぜこの問題が発生するのですか、何か考えはありますか？

Maven例外

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-war-plugin:2.2:war (default-war) on project ferpasys_webapp: Error assembling WAR: webxml attribute is required (or pre-existing WEB-INF/web.xml if executing in update mode) -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException