Add html_url attribute to comments.

html_url attributes were missing from IssueComment and PullRequestComment.
Added to both as per the GitHub API.
Add tests for html_url for Issue and PullComment (#170)

I just modified the ReplayData manually and added a "get" in the tests.
Merge branch 'topic/Pull170' into develop
Merge branch 'develop'
Publish version 1.16.0