Collective Ops Part 1

The basic interface definitions, local-only versions of remote-access,
param-resolution, device-resolution and mgr.

A collective op is able to execute synchronously across devices
and across separate graphs. Collective ops to be introduced eventually
include broadcast and all-reduce.  This change is part of a series of
changes that will introduce the necessary infrastructure then the
initial op implementations.

PiperOrigin-RevId: 190860248