Missing stubs for configparser in python 2 and six

[timabbott]

While #116 added configparser for Python 3, it looks like we're still missing configparser on Python 2, and also six.moves.configparser.

[euresti]

Unless you're talking about something else in Python 2 it's called ConfigParser and it's there now.
And I just added it to six.moves in #937

[timabbott]

Nice, yeah, I think #937 resolves this.