Add fragment requirements to p2.inf file of product feature
Move ValidationModule from impl to runner package
Make all API Enitity classes Serializable
Add standalone setup classes for Forge validation and publishing
(GEP-212) Create a Geppetto uber-jar with shaded entries

This commit adds a new Maven module that uses the maven
'shade' plugin to avoid conflicts in com.guice.inject and
org.antlr when using Geppetto in a Jenkins instance. This
jar is needed since the 'maskClasses' functionality provided
by the hpi plug-in seems to be ignored when running on
Jenkins slaves.