Consolidation of XMLTestCase as a preparation for adding tests of referencing XML objects.
Added some JAXB annotations for referencing objects and fixed the RS_Identifier adapter.
Added a partial test case for PrimeMeridian as a proof of concept.


git-svn-id: https://svn.apache.org/repos/asf/sis/branches/JDK7@1546682 13f79535-47bb-0310-9956-ffa450edef68