fixed the multi-line issue for criterion prompt, criterion option text,
peer assessment feedback and self assessment feedback.

TNL-814
Code refactoring after PR code review.

TNL-814
Merging master into this branch
Code refactoring after PR code review.

TNL-814
Minor code refactoring.

TNL-814
Merge pull request #636 from edx/muzaffar/tnl814-multiline-issue-ux

fixed the multi-line issue for criterion prompt, criterion option text,