* jobspec: rename node pool scheduler_configuration
In HCL specifications we usually call configuration blocks `config`
instead of `configuration`.
* np: add memory oversubscription config
* np: make scheduler config ENT
Implements the HTTP API associated with the `NodePool.ListJobs` RPC, including
the `api` package for the public API and documentation.
Update the `NodePool.ListJobs` RPC to fix the missing handling of the special
"all" pool.
