Consider moving the Gerrit user documentation into the committer handbook
Submitted by Wayne Beaton @wbeaton
Link to original bug (#512339)
Description
I don't think that the handbook includes a link to the Gerrit documentation in the wiki:
https://wiki.eclipse.org/Gerrit
We should at least include a link.
I'd also like to consider moving the documentation into the handbook. My primary concern against doing so is that updating the handbook is somewhat more involved than updating the wiki.