Add rights for engine to call getAssignedServices

Engine/dispatcher needs this method for resolving ExecService-Facilty
pairs from audit message.
Fix permissions check in services

If target file is symlink, permissions is checked on linked file (not on
symlink itself)

Affected services: fs_home, k5login and passwd_scp
New model ResourceState

- added new class ResourceState
- added method getResourcesState
GUI: when creating Facility always pass backup list

- Pass content of "backup list" from list of Facilities when
  creating new Facility, since simple "list" might be empty/filtered.
Merge pull request #402 from zlamalp/gui

GUI: when creating Facility always pass backup list