STANBOL-488: implemetnation of chain scoped enhancement properties for 0.12.1; Chain scoped Enhancement Properties are stored as RDF within the execution paln. Added Helper Methods for doing so to the ExecutionPlanHelper. EnhancementProperties do now consider chain scoped properties. Adapted the helper methods in the EnhancementEngineHelper accodringly. Added enhancement properties support to the list, weighted and graph chain.

git-svn-id: https://svn.apache.org/repos/asf/stanbol/branches/release-0.12@1593490 13f79535-47bb-0310-9956-ffa450edef68