Remove the '.' preceding the RC segment for the python version string

PEP 386 indicates that there should not be a '.' before the release
candidate characters.

Change-Id: If4a642a3749591ac2b88ca87097fbd631df9377e
Merge topic 'SIMPLEITK-508_RemoveDotBeforeRCForPEP386' into next

1f0ef71e Remove the '.' preceding the RC segment for the python version string