First read the github pull request explanation
A pull request also generates an issue in your projects issue tracker.
Making comments that are associate with a line is a cinch.
When in the discussion area, line comments have a special icon to tell readers that this comment is
tied to a specific line in a file. If you click on the fileName:LXXX link then you will be forwarded
to the line in question, and the comment.
The discussion area is great for communicating about specific changes in the pull request that need
to take place before the request will be accepted. Also there is a button at the lower part of the
page that you can use to perform the merge (if it can be performed cleanly).
