Use superclass read/write functions if possible
Add minimal tests of read/write with a subclass
Adding autoclass_content=both to sphinx conf
Add funcs to convert table cols to/from unicode/bytestring
Skip doctests for these conversion functions
Tentative fix for issue #2401: more informative error message when vstacking tables with incompatible columns.
Raise TypeError instead of AssertionError
Removed all asserts from modeling and raise errors instead
fixed test failure
Change some TypeError to ValueError
Removing unnecessary lines
Fix pep8 compliance and reword the assertions in the tests, as suggested during code review.
Fixing documentation links and warnings in cosmology
improve printwcs, add a test
Merge pull request #2444 from bluescarni/bugfix-for-issue-2401

Tentative fix for issue #2401
Small heading link fix
Fix slow down in Angle.__new__
Merge pull request #2456 from bsipocz/fix_cosmology_docs_links

Fixing documentation links and warnings in cosmology
Update CHANGES.rst

Moved this from the wrong section.
Recify 54ed32c1c3c1e16de34a212d5621fe824746af3b which was written before 92aab898f9ea64bac1dfc64531af7346e48213e8--the __repr__ and __str__ still relied on the SIP and InverseSIP models being based on the composite model class which is no longer the case.