coveralls send me mails when contributing

[buhtz]

Please see this example
bit-team/backintime#801

This is not my repository. I just contributed some code with a PR. Coveralls is checking that code - this is nice. But it sends me an email about it.

Is there a way to setup coveralls that it only comments into the PR but not sending out a mail?

[sebright]

It would also be nice if Coveralls edited its original comment instead of creating a new comment for every change to the pull request. Then users would only receive one Coveralls e-mail per pull request.