Switch to using ez_setup.py, and simplify setup.py, following recent changes in Astropy core.
Updates to __init__.py to match Astropy core
Minor fix
Added backward compatibility with Astropy 0.2
parallel option can only be used with Astropy 0.3 or later
Re-organize the setup.py so that Astropy is not required for egg_info
Merge pull request #30 from astrofrog/update-setup-files

Updates to package template following updates to Astropy core