No mass assignments
Other models are uninteresting for ma's
Fixed test
Now is not after next month (the challenge used to test with was not the right challenge)
Merge branch 'updateviews' into mass_assignment
Moved challenge views to haml, removed unused status views/actions
Removed tests for removed views
Updated navigation
Fixed enroll feature
Merge pull request #119 from boersmamarcel/mass_assignment

No evil mass assignments any more
Removed unused placeholder image library
Removed haml comments
Merge branch 'reviewchallenge' of https://github.com/boersmamarcel/challengesplatform into updateviews
Merge pull request #121 from boersmamarcel/updateviews

Updated views and some more