more installation instructions for ipython that were missing in previous commit
more installation instructions for ipython that were missing in previous commit

sdss/marvin,sdss/marvin,bretthandrews/marvin,albireox/marvin,bretthandrews/marvin,sdss/marvin,bretthandrews/marvin,bretthandrews/marvin,sdss/marvin,albireox/marvin,albireox/marvin,albireox/marvin