Multiple process workers support for nova-scheduler.
Since blueprint placement-claims in Pike, the FilterScheduler
uses the Placement service to create resource allocations (claims)
against a resource provider (i.e. compute node) chosen
by the scheduler. That reduces the risk of scheduling collisions
when running multiple schedulers, so this change adds the ability
to set multiple scheduler workers like for the nova-osapi_compute
and nova-conductor services.
Co-Authored-By: Matt Riedemann <mriedem.os@gmail.com>
Change-Id: Ifdcd363d7bc22e73d76d69777483e5aaff4036e3