Merge pull request #25 from SamLau95/seeQuestion

See question
Merge pull request #26 from SamLau95/viewStudents

View students (not done yet)
Update Ruby and Rails version
Migrations
Merge branch 'master' into rails-ruby-version
Merge pull request #28 from SamLau95/rails-ruby-version

Rails ruby version
Annotate QuizLock
Quiz 1 is not a draft
Add associations to quiz lock
Approving request also locks student to a quiz
Association and only pick published quizzes to give
Association for student
Use approve_and_lock!
Lock and destroy instead of approve
Use quiz lock to determine whether request approved
Factory for quiz lock
Fix typo
Renamed method
QRs do not have approved attribute
Fix failing tests