Merge pull request #2492 from minrk/pygments_setup

add missing 'qtconsole' extras_require

The docs mention `easy_install ipython[qtconsole]`, but that would fail because it was undefined.  It now implies the pygments extra dependency described in the docs.

setup.py

@@ -230,6 +230,7 b" if 'setuptools' in sys.modules:"
     setuptools_extra_args['entry_points'] = find_scripts(True)
     setup_args['extras_require'] = dict(
         parallel = 'pyzmq>=2.1.4',
+        qtconsole = 'pygments',
         zmq = 'pyzmq>=2.1.4',
         doc = 'Sphinx>=0.3',
         test = 'nose>=0.10.1',