Switch to Python 2+3 Rudolf, thanks @iknite
Switch to Python 2+3 Rudolf, thanks @iknite

Makes 'nosetests --with-color tests/' work under Python 2+3.

Fixes RuntimeWarning when running 'nosetests tests/' under Python 3:
/Users/pzrq/.virtualenvs/fabric343/lib/python3.4/site-packages/nose/plugins/manager.py:395: RuntimeWarning: Unable to load plugin color = rudolf:ColorOutputPlugin: invalid syntax (rudolf.py, line 787)

rodrigc/fabric,mathiasertl/fabric,ploxiln/fabric