Add: errorHandler that handles mongo validation errors + user defined errors
Implement new error handler in some places
Merge branch 'feature/error-handler' into develop
/api/bookings endpoint tests work
Bugfixes + test runners
Get tests to work
Merge branch 'develop' into feature/rest-api-test

Conflicts:
	app/scripts/app.coffee
	test/karma.conf.js
Klass endpoint tests
Clean up specs & test config
Fixes issue #49
Fixes issue #50, so the date has to be in past time
Fixes issue #48
Merge branch 'feature/bugfix' into develop