x/build/cmd/gopherbot: add author to issue notification comments

[josharian]

gopherbot generates the "CL mentions this issue" issue comments:

https://github.com/golang/build/blob/4639cd3919e4243a672a11a56543004bf1778326/cmd/gopherbot/gopherbot.go#L811

It currently includes a link to the CL and the CL title. It'd be nice if it also included the CL author's name or handle. Maybe: "Change <link> by <author> mentions this issue: <title>".

[iamoryanmoshe]

I'll take a crack at it

[gopherbot]

Change https://golang.org/cl/127930 mentions this issue: cmd/gopherbot: change issue notification comment to include author name

[iamoryanmoshe]

Or not

[gopherbot]

Change https://golang.org/cl/181977 mentions this issue: cmd/gopherbot: add the author of the change to the notification on github