Code Review and Q&A topics: Add date and author of edited comment

As a user I'd like to know the name and date of comment changing. Also I'd like know why it was happened. So I can be sure if it's me or not
We should to add date/time of comment editing, in the same manner as it works for topics
Acceptance criteria:

• User which has EDIT_OTHERS_POSTS permission should be able to edit other comments if someone posts inappropriate content; ;
• User should see the date and name user who was editing comment;
• All information about editing should be displayed below the comment's text.