Revert "remove unneeded dependencies for org.jboss.tools.hibernate3_5"

This reverts commit 7fea04796caafed21605038804e5d94d50f2273a.
use org.hibernate.util.StringHelper in org.jboss.tools.hibernate3_5
use org.hibernate.util.ReflectHelper in org.jboss.tools.hibernate3_5
remove dependency on org.eclipse.ui.views for org.jboss.tools.hibernate3_5
remove IHQLCompletionHandler.getCompletionProposals()
remove unused IHQLCompletionHandler.clear()