docs(CONTRIBUTING): add note about TravisCI badge
fix(e2e): remove innerHTML patching hack

Previously an issue with the patching in ngHintDom caused infinite recursion
when attempting to log messages to a div to be read by protractor. After updating
the ngHintDom dependency, this hack can be removed.

Closes #24
test(e2e): update exclusive example now that ngHintDirectives is usable
feat(ngHintDirectives): add ngHintDirectives to available ngHintModules