Added option of retrieving services from rls-services document by uri

darcs-hash:20081126165255-1e3d8-eac58e18d81c9694d9af87232535f792b2912af1
Added forgotten registers of XML classes

darcs-hash:20081126165335-1e3d8-151f404c02a7659301b939b0f80cdd09c7d55e66