Views: Pig and Files view no longer need to include dependency classes

Views can now include dependencies as jars by including the jars in WEB-INF/lib folder of the view.

The Files and Pig views currently do ...

<descriptorRef>jar-with-dependencies</descriptorRef>

...for the maven assembly plugin in the pom.xml.

This works but includes all of the dependency classes into the view archive including the ambari-view classes.

Instead of using jar-with-dependencies we should just put the required dependency jars into the WEB-INF/lib of the view archive.