Documentation update

[cnaw]

When installing MMTtools in addition to astropy I had to manually
pip install photutils ccdproc

Although I thought these would be part of astropy, they apparently are not. Once these are
installed
python setup.py install in MMTtools works like a charm.

[astrochun]

Welcome to GitHub!

@cnaw, thanks for pointing this out. The documentation is outdated as a setup.py script is available and ccdproc and photutils are included.

Thus, the following will install the appropriate software:
python setup.py develop

However, photutils and ccdproc are not used by the mmirs_pipeline_taskfile. Ultimately, I would like to refactor the code so that mmirs_pipeline_taskfile is its own package.