Merge util into assignment_preprocessor.py
Clean up and reorganize assignment preprocessor
Add some initial tests for assignment preprocessor
Add more assignment preprocessor tests
Don't depend on numpy in assignment preprocessor
Add requirements.txt
Add .travis.yml
Move ipython installation into before_install
Use correct ipython installation
cd back into nbgrader dir
Don't use --user in ipython install
Install zmq dependency
Remove score.py
Use apt-get with sudo
Remove score from __init__.py, too
Fix nosetests invocation
Add coverage information for coveralls
Add badges to README
Merge branch 'cleanup'