Fix integer overflow np.product
Use the system monospace font in the docs
Fix memory leak in WCS reported in #2754
Add changes entry.
Allow for custom datatype names in votable

This should allow end users to workaround VOTable files that contain
invalid datatypes.

Also adds two datatypes seen in Vizier tables: "unsignedInt" and "unsignedShort".
Update docs about datatype mappings.
Add changes entry.
Forced rebuild because of merge issues with astropy_helpers

* The commit history where astropy_helpers accidentally got
  modified is making rebasing off of master really messy, so
  rebuilt from current.
* CHANGES.rst not modified, so this is *not* ready to go.
  Should wait on 0.4 to shake out before updating that.
Update CHANGES to include cosmology clone operation

* Placed in 1.0 section
* Closes #2592
Quantity: Convert numerical objects such as decimal.Decimal to float by default
Rewrite Distance initializer so it can take lists of quantities.
Put back in automatic unit selector for distmod with array support
Implementation of wcs_to_celestial_frame
Minor improvements
Make wcs_to_celestial_frame extensible
Added tests and docstring for ``wcs_to_celestial_frame``
Skip doctest
Added changelog entry
Merge pull request #2754 from mdboom/wcs/memleak

WCS memory leak
Merge pull request #1419 from mhvk/quantity-init-with-objects

Cannot create Angle objects with decimal.Decimal