Add Travis and Coveralls badges to README
Merge pull request #17 from singingwolfboy/readme-travis-coveralls

Add Travis and Coveralls badges to README
Adds support for passing JSON parameters to initialize XBlock
Merge pull request #18 from edx/xblock/args

Adds support for passing JSON parameters to initialize XBlock
Use Makefile to install requirements and run tests
Useful repr for xblock state
Adds a list which shows a list of users

distinct() isn't supported by sqlite. Hence the funny code.

PR feedback
Merge pull request #22 from edx/pmitros/useful-repr

Useful repr for xblock state
Merge pull request #19 from edx/will/makefile

Use Makefile to install requirements and run tests
Merge pull request #23 from edx/pmitros/userlist

Adds a view which shows a list of users
Properly make a request a POST for a test
Support for pyfilesystem field (and minor PEP8+test cleanups)
Merge pull request #21 from edx/pmitros/pyfilesystem-refactor

Pyfilesystem support. Also: 
* Support for XBlocks refactor
* PEP8 fixes
* Fix for one failing test-case from Ned. 
* Selenium test (workbench.test.test_problems.ProblemInteractionTest) is still intermittent. Works on my machine. Sometimes works on Travis, sometimes fails.