working in progress with adding more tests
Merge branch 'AccessControl' into 73206422
change of disabling link
update editsaveAction to ensure that at least one instructor is able to delete the course
adding tests
completed more tests
Merge branch 'AccessControl' into 73206422
update equalizerIrrelevantData
refactoring and adding tests
Merge branch 'AccessControl' into 73206422
update instructorDb
udpating instructorsDbTest: not using deprecated APIs anymore
update instructorsLogic
Merge branch '73206422' into AccessControl