<plugin>
     <groupId>org.apache.tomcat.maven</groupId>
     <artifactId>tomcat7-maven-plugin</artifactId>
     <version>2.2</version>
     <configuration>
          <server>myTomcat</server>
          <url>http://localhost:8080/</url>
     </configuration>
</plugin>

<server>
    <id>myTomcat</id>
    <username>admin</username>
    <password>admin</password>
</server>

<role rolename="tomcat"/>
<role rolename="manager-script"/>
<role rolename="manager-gui"/>
<role rolename="admin"/>
<user username="admin" password="admin" roles="tomcat,manager-gui,manager-script"/>