cmd/coordinator: use a smaller instance type

Also, hard-code the IP, and request the "allow-ssh" tag.

Change-Id: I6b0af0a8a8dbb358c55226f87fd7f8613a88da43
Reviewed-on: https://go-review.googlesource.com/5240
Reviewed-by: Andrew Gerrand <adg@golang.org>
2 files changed