travis, run migrate after load scheme

if there is new migrate, it might not be reflected in the schema
update schema
test cases for announcement creation and editing
Add coveralls
Add coveralls and travis badges
add type for describe
Merge pull request #267 from jsyeo/jsyeo-add-badges

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

Add coveralls
more tests for announcement editing
change expiry_at to parameters
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
Merge pull request #5 from Coursemology/development

Merged latest test cases from main repo