pygraphviz 1.3 release candidate

[Aric Hagberg]

Hi Everyone - There is a new release candidate for pygraphviz -
pygraphviz-1.3rc1.
This version has Python 3 support and other small fixes.

You can download it from
https://pypi.python.org/pypi/pygraphviz/1.3rc1

Please test it out and send your comments here, or open an issue at
the github site https://github.com/pygraphviz/pygraphviz

Aric