CORE,REGISTRAR,RPC,GUI: privilege fixes for VOOBSERVER

CORE:
- Added privilege to list vo's groups and vo/resources tags.

REGISTRAR
- Added privilege to list applications of VO/Group/Member.
- Added authz for getting application form item.

RPC:
- Registrar interface changes (pass session).

GUI:
- Fixed authz in various places, disabled some more action buttons.