First commit of Healpix density map creation code
First commit of BOSS data description notebook
Merge remote-tracking branch 'origin/bruno_cats2healpix' into test_merge
merging with Bruno's branch. doc folder has a pynb file.
Additional information on weights
Merge branch 'bruno_cats2healpix'

Additional description of weights, creating a test md file from an ipython notebook.
Testing ipynb to md format conversion
Merge branch 'bruno_cats2healpix'