Merge pull request #120 from keflavich/hdu_method

Add an 'hdu' convenience method to Cube
Merge pull request #121 from keflavich/bugfix_getitem_mask

Bugfix: Can't index _mask if it is None
Update CHANGES.rst
added CLASS LMV reader
added class format to reader, auto-format-determinator
LMV reader updated, tested on real files
fix headers in class_lmv
make apply_along_axis public and have it return a projection

cleanup
more cleanup, but also note that the previous commit renamed
"apply_along_axis" to "apply_function", which is more accurate
fix test: unnecessary comma added
fix return type from _apply_numpy_function.   Now that I think about it,
that should probably be made public too
make apply_numpy_function public and have sum, min, max return
projections by default

forgot an underscore

whitespace