Conference service and GRPC interface
Created by: UlfNorell
Adds two applications:
- nynja_grpc for managing grpc requests
- conference handling the new conference scheduling
Protocol in: apps/conference/priv/proto/conference.proto
Currently does not talk to the call bridge. Instead placeholder messages are posted to the group for 5 min precheck and autodial.
Also not implemented:
- recurring meetings
- overlapping meeting check
- time zone API
- tests!