Fixed issue #771.Comment allow new line.

Raising Fresh PR on issue #771 as my previous branch got messed up while pushing from local.
I have tested all scenarios from my end. 
The comment div is taking care of next line.
In case of edit it accepts new line and on hitting enter it goes to next line. to post the changed comments user will follow same ctrl+enter.
Based on our discussion yesterday I thought of keeping it separate by adding another argument. But will check how to add in the existing opts.