* introduce some type aliases for round and set-id
* overhaul session "changed" flag and document better
* do_initialize in BABE when getting new session
* grandpa module tracks set IDs
* update runtime versions
* doc comment -> comment
* Include docs fixes from Gav
Co-Authored-By: Gavin Wood <gavin@parity.io>
* some more review changes
* fix srml-grandpa compilation