* Update setup.py requires and classifiers
* Drop Python 2.7 and 3.4 from CI
* Update docs dropping 2.7 and 3.4 support
* Fix mock imports and remove tests related to pypi's mock module
* Add py27 and 34 support docs to the sidebar
* Remove usage of six from tmpdir
* Remove six.PY* code blocks
* Remove sys.version_info related code
* Cleanup compat
* Remove obsolete safe_str
* Remove obsolete __unicode__ methods
* Remove compat.PY35 and compat.PY36: not really needed anymore
* Remove unused UNICODE_TYPES
* Remove Jython specific code
* Remove some Python 2 references from docs
Related to #5275
The help for the '--runxfail' flag is somewhat misleading. The default
behaviour is to run tests marked as 'xfail' but to ignore the results. This
flag alters that behaviour by running these tests as if they weren't marked
'xfail', i.e. their results are not ignored.
Less hacky way to make XPASS yellow markup. Make sure collect reports still have a "when" attribute.
xfail changed to XFAIL in the test report, for consistency with other outcomes which are all CAPS
