Added example exercise that has file attachments
Merge pull request #144 from LassiHaaranen/master

Added example exercise that has file attachments
Only show assistant feedback when assistant grading is allowed
Merge pull request #145 from LassiHaaranen/master

Only show assistant feedback when assistant grading is allowed
Merge remote-tracking branch 'upstream/master'
Merged old branch, using external_services these days..