webadmin: Remove irrelevant operations from UserVmManager role

Operations ActionGroup.MOVE_VM, ActionGroup.MIGRATE_VM are detached from UserVMManager role

Change-Id: I4e85bf9adce32e6f60cec02a036d8c7798aba8a0
Bug-Url: https://bugzilla.redhat.com/885132
Signed-off-by: Libor Spevak <lspevak@redhat.com>