* Look up servers less often, don't hit API for missing auth events unless there are actually missing auth events
* Remove ResolveConflictsAdhoc (since it is already in GMSL), other tweaks
* Update gomatrixserverlib to matrix-org/gomatrixserverlib#254
* Fix resolve-state
* Initialise t.servers on first use
* Add resolve-state helper
* Tweaks
* Refactor forward extremities, again
* Tweaks
* Minor optimisation
* Make path a bit clearer
* Only process state/membership if forward extremities have changed
* Usage comments in resolve-state