Merge pull request #1884 from astrofrog/fix-xrange

Fix use of xrange with Python 3
Conflicts:

	astropy/table/table.py
Try Numpy 1.8.0 for the docs build specifically so that it is compatible with the wheel we've built for matplotlib.
Merge branch 'v0.3.x' of github.com:astropy/astropy into v0.3.x