Admin: Prevent options which don't make sense from being selected

Created by: iainbryson

While working on the bugs, I had an idea about the usability.

There are several buttons which don’t make sense depending on the status of the quiz: if there are no errors, view errors doesn’t make sense. If there are no submissions, why can you click on submissions. If there are errors, you can’t View as student or Teacher. And if there are errors, maybe selecting the quiz should force the user to click on View Errors.

So. In those cases, should we disable the buttons? In fact, if we don’t select a quiz, why let a user click on any of the buttons? Maybe with a hover tooltip saying “select a quiz” to guide the user.