Sprint: Added new external resources page, link from main and content pages
DOC annotate is now in numpydoc format
DOC fix typo in the annotate method
Add namespace package mpl_toolkits to package meta-data
Merge pull request #2208 from NelleV/MEP10_annotate

DOC annotate is now in numpydoc format
Fixing small typo in the plot tutorial.
Fix for false detection of gtk3
Merge pull request #2215 from josericardo/master

Fixing small typo in the plot tutorial.
Typo
Merge pull request #2220 from felipeacsi/master

Fixing typo in docs
MEP10 axhline and axvline are now in numpydoc format
DOC modified sphinx's layout.hml

The previous sphinx layout relied on overriding a default template.
It meant we could not easily add links and other things in the header.
The new layout does not inherit from anything, hence makes it easier
to tune.
DOC the space between titles and the rest is now bigger
DOC improved spacing between functions, classes and the rest
Merge pull request #2209 from NelleV/MEP_axhline

MEP10 axhline and axvline are now in numpydoc format
Merge pull request #2186 from NelleV/doc_styling

DOC modified sphinx's layout.hml
Merge pull request #2210 from efiring/namespace

Add namespace package mpl_toolkits to package meta-data
Merge pull request #2217 from AdamHeck/master

Fix false detection of gtk3 bindings during install
Try PySide then PyQt4 for Qt4 examples.
Use the correct connect method for PySide.

This should make the examples work with both PyQt4 and PySide (I can only test the later)
Use the same logic as MPL uses when picking Qt interface.

Thanks to Michael Droettboom (https://github.com/matplotlib/matplotlib/pull/2221#issuecomment-21108901)