* substitute '@@' code block delimiter with triple back-tick, more consistent with other markdown extensions
* remove development print and allow spaces between triple backtick and syntax name in codeblock
* update comparison content for markdown test
* add 'docstrings-with-pygments' feature without packages checks and tests
* move syntax_highlight doc filter in compatibility module and define it conditionally
* typo fixed
* add test for optional code highlight ('pygments' and 'markdown' packages must be installed)
* Get rid of runtests.py
* Moved test code from rest_framework/tests and rest_framework/runtests to tests
* Invoke py.test from setup.py
* Invoke py.test from Travis
* Invoke py.test from tox
* Changed setUpClass to be just plain setUp in test_permissions.py
* Updated contribution guideline to show how to invoke py.test