changed 'osc request revoke' to prevent set same state twice

changed 'osc request revoke' to prevent set same state twice

Changed 'osc request {reopen,accept,decline,wipe,revoke}' to check
the current state and ask the user if the requested state is the
same as the current state of the request. This should prevent e.g.
useless state changes (set to revoke multiple times in a row) by
accident.