Fix the test for an unedited astropy 0.3.2 config

Ignore the jquery_url line when calculating md5sum.
Modernize jsviewer configuration items.
Restore io.fits and io.votable options
Fix error message about moved configuration items.
Add CHANGES entry.
Merge pull request #2772 from mdboom/config/issue-2772

Configuration warnings with clean 0.3.2 -> 0.4 upgrade