Added AbstractRoutingContentStore as a start base implementation.
Added warnings to drive config away from disused setTransactionService towards setRetryingTransactionHelper.
git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@5734 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261