Remove broken link

One of the link containing more information on the function `super()`
was broken. Fixes #1376
Skip doctests that require a remote server
Add support for REMOTE flag to doctests.
Document new REMOTE flag in doctests.  Remove out-of-date information
about doctest flags remaining in the output.
Mark some doctests as +REMOTE
Remove spurious warning from printwcs, as reported by Maik Riechert on astropy@scipy.org
Add changelog entry.
Merge pull request #40 from mdboom/docs/disable-remote-doctests

Add REMOTE flag to doctests so we can disable tests that require remote data
Added known issue for MAGEIA-2 and 3 install bug
Updated wording following @embray's suggestion
Added a comment to remind ourselves that e-terms should indeed be computed using the equinox, and not the observing time/epoch.
Merge pull request #1496 from astrofrog/clarify-eterms

E-term calculation uses equinox but should use observation date
Merge pull request #1853 from astrofrog/mageia-known-issue

Mageia known issue
Renamed doctest +REMOTE option to +REMOTE_DATA
Update CHANGES.rst

Fixed extra indentation
Merge pull request #1843 from astrofrog/disable-remote-doctest

Skip doctests that require a remote server
Merge pull request #1819 from gabraganca/super_docs

Remove broken link
Merge pull request #1845 from mdboom/wcs/hide-warning-in-printwcs

Remove spurious warning from printwcs
Add no-heading option to the automodapi sphinx ext

This add the option to not have the auotmodapi extension add a top
level title, i.e `astropy.nddata Module`.
couple of docstring typos