SF patch 1179503:  Fix typos in rpc.py
SF patch 1179503:  Fix typos in rpc.py

* Call to unpack_int() should have no arguments
* Misspelled BadRPCVerspion exception
* Replace <> with !=

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator