py3: update ssh for base64.b64decode raising binascii.Error instead of TypeError A command like: python -c 'import base64; base64.b64decode("QQ")' would fail in Python2 with: TypeError: Incorrect padding but in python3: binascii.Error: Incorrect padding

# requirements.txt file for use as "pip install -r requirements.txt" as a
# readthedocs compatible alternative to "pip install -e ." which is a working
# alternative to "setup.py develop" which doesn't work with Mercurial 3.7
.