Would be great to have GCE snapshot management implemented in GCE-plugin.
In many cases, users want to persist failed tests, and keeping slaves for them for an extensive amount of time seems like an expensive and not very efficient solution.
It would be much more efficient to trigger snapshot creation by failed jobs/tests, with configurable parameters such as trigger events, snapshot lifespan, naming patterns (e.g. label + timestamp or "latest") etc. that could be re-used to restore VMs.