Write output sky map as FITS file
Added check for clusters with too-few points.
Ensure that points passed to posterior are 2D array
Merge pull request #2 from lpsinger/write_fits

Write output sky map as FITS file
Moved to package subdirectory, added Sphinx docs.
Removed test for BIC(1) > BIC(2), ensuring that algorithm will at least consider up to four clusters.