travis, run migrate after load scheme

if there is new migrate, it might not be reflected in the schema
update schema
Add coveralls
Add coveralls and travis badges
Merge pull request #267 from jsyeo/jsyeo-add-badges

Add coveralls and travis badges
Merge pull request #266 from jsyeo/jsyeo-coveralls

Add coveralls
Ignore coveralls coverage directory
Merge pull request #270 from jsyeo/jsyeo-coveralls

Ignore coveralls coverage directory
[testing] add controller test helper
fix typo in course model
[testing] move mission page test to features test dir
Merge pull request #268 from wangqiang1208/test/hackathon-tests

test cases for announcement creation and editing
Merge branch 'development' of github.com:Coursemology/coursemology.org into development
disable grading saving button after submit to prevent duplicate requests
Merge pull request #273 from wangqiang1208/test/hackathon-tests

re-write announcement test cases( refine coding style )
Merge pull request #274 from wangqiang1208/bugfixing/gradings-saving-double-clicking-duplicate-requests

disable grading saving button after click submit to prevent duplicate requests
remove all compiled assets
Merge branch 'development' of github.com:Coursemology/coursemology.org into development
set server static assets to true in development
parse creator as argument to course, now we can directly create course, no need through UI