(core) AdhocRequest definition
(core) An actor for handling one-off requests
(core) A test for the adhoc request actor
(core) WIP refactoring data capture
(core) Consolidate the two Request types into one.

The feature-terminating-schedules work allows us to consolidate the
persistent and adhoc requests.
(core) Move old actor spec
(core) RequestActor should start on initialisation
(core) Props for the new RequestActor
(core) Remove the old polling actors
(core) Consolidate the 2 actor specs
Merge branch 'feature-adhoc-requests'