Adding mplot3d's tests to the default test suite
toolkits_tests subpackage is now a thing
Fix travis.yaml
Merge pull request #3228 from tacaswell/top_level_docstring

DOC : top_level doc-string clean up
Merge pull request #3230 from tacaswell/offset_doc_round2

DOC : added note about useoffset rcparam
Merge pull request #3154 from WeatherGod/mplot3d/whitelist_tests

whitelist mpl_toolkits tests
Merge pull request #3188 from tacaswell/np_error_patch

Np error patch
Fix auto-closing in PolyCollection
Merge pull request #3236 from mdboom/pep8-tests-in-separate-config

Test PEP8 stuff in separate Travis build.
Merge pull request #3193 from QuLogic/multi-option-plot_directive

Fix plot directive when used with multiple options.
Add test png
Merge pull request #3239 from mdboom/polycollection-closed

Fix auto-closing in PolyCollection
both are good distributions
conda libpng and freetype don't help
Remove dregs of nxutils
Fixed backend workflow.
working on guide for choosing colormaps. Have overview section and start on a few others.
added colormaps guide to beginner guide
Merge pull request #3004 from mdboom/docs-nxutils

FAQ and unit/ still refers to nxutils
Merge pull request #3246 from dmcdougall/fix-doc-links

Fix some hyperlinks in the documentation

Edits only in rst files