Fix for STANBOL-995:
-The name of the contentitem.ftl template has been changed to contenthubcontentitem.ftl to avoid the conflict between this one and the one in the Enhancer.
-ContentItemResource has been taken from the Enhancer. Contenthub has its own copy of this class not to depend on Enhancer Jersey module.

git-svn-id: https://svn.apache.org/repos/asf/stanbol/trunk@1460665 13f79535-47bb-0310-9956-ffa450edef68