removed edit question button from course home page

if the user doesn't have authorization to edit the question
(similar to the mechanism used in the question view page)
implemented users cannot comment until they judged the required

number

Users cannot comment answers until they have judged the required
number of times. If they somehow found their way to the creation
page, they will be redirect to the question page. Currently,
users can still comment and view comments for questions.

I have moved the "required_rounds" to the judgement module.
modified the condition to prevent commenting answers

Now, instructors and admins can comment even if they haven't
judged enough times. This only makes since they may not submit
any answers but still want to comment the students' answers.