add 'save' to quicklooks
with_mask checks for broadcastable, not equal shape
clean up tests of broadcastability
Merge pull request #166 from keflavich/quicklook_save

Minor fixes: quicklooks, with_mask test
bugfix: with_mask should be usable when no `_mask` is defined
Merge pull request #172 from keflavich/with_mask_no__mask

bugfix: with_mask should be usable when no `_mask` is defined
update apt-get listings (fixes graphviz install issue)
First attempt at CASA mask output.
Added docstring.
Add warning for image appending.
Check for inputted image.
Need to transpose mask for CASA
Added changelog entry.
Add option to re-add Stokes axis.
Docstring for add_stokes
Added making CASA masks to docs.
Use int16 instead of float64.
Fixed merge conflict.