CBD-926: Use support@couchbase.com as bug address

Our fork is no longer following the upstream project closely
so it's better to have people reporting bugs to us

Change-Id: Id7c02701cb900b6722800750e0bb5bf7220e5257
Reviewed-on: http://review.couchbase.org/25359
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Tested-by: Trond Norbye <trond.norbye@gmail.com>