cmd/coordinator: resize kubernetes instance group down to one after 10min idle

And the associated gceutil change used by this CL was:
https://review.gerrithub.io/#/c/254054/

Change-Id: Id493a2ffaf9e706096e920a19b828fa85d41821a
Reviewed-on: https://go-review.googlesource.com/17315
Reviewed-by: Evan Brown <evanbrown@google.com>
2 files changed