ref: Rename package ipc to rpc.

We are doing this because rpc better describes what we are offering.
Also now vrpc and rpc are more obviously related.
This has the potential downside of being confused with the go rpc package
but we believe the two packages will ralrely be used together..

MultiPart: 6/11

Change-Id: Ia5c35cb7938ac907be418b495f485aede3621e56
291 files changed