added some extra tests to studygroup model
Fixed "invalid Date error"
Merge branch 'master' into edit_studygroup
Fixed location is nil bug

Conflicts:
	app/models/studygroup.rb
Merge branch 'edit_studygroup' of https://github.com/dkumar/MeetMyClassmates into edit_studygroup

Conflicts:
	spec/requests/studygroup_new_spec.rb