* Clean roomserver consumer

* Make account data sync incremental

* Use a different name for the sync AD table

* Improved error logging

* Created missing topic in tests

* Add client API topic to tests

* Add client API topic to common

* Move data batch retrieval

* Add database index for data retrieval

* Fix typo in table name

* Fix indentation

* Use gomatrixserverlib function to split user ID

* Propagate profile update via m.room.member events

* Send profile data on room join

* Send profile data on room creation

* Rename variable

* Move membership update to roomserver consumer

* Improve iteration

* Move event update from client API server to sync API server

* Change the way buildMembershipEvents is called

* Forbid update of someone else's profile

* Use gomatrixserverlib method

* Fix depth and previous events not being set

* Fix wrong removal in latest commit

* Update all events instead of only memberships

* Handle case where there is no state key

* Fix test

* Use utility methods from gomatrixserverlib, rather than reimplementing them

* Return string rather than pointer to string

* Update gomatrixserverlib

* Fetching missing state from the roomserver.

Whenever the syncserver receives an event from the room server that adds
state that isn't in the syncserver's local database it should fetch
those state events from the roomserver.

* Fix append

* Put comment back

* Comments

* s/addsStateEvents/lookupStateEvents/

* Fix spelling

* Include the stream position that a state event was added at in the current state tables

* Fix comment

* Review comments

* Add test for transition to leave

* Add test for join/leave in the same /sync response

The logic required to populate the right bits of `RoomData` tends towards
the complete `/sync` response struct, so just use the actual response struct
and save the hassle of mapping between the two. It may not make much difference
in its current form, but the next PR will make use of this.

This PR has no functional changes.

This is only 'mostly' correct currently, because what should be no-op dupe
joins will actually trigger the entire room state to be re-sent.

Bizarrely, it's significantly easier to just do that than work out if we should,
and there are no client-visible effects to doing so, so we just do it for now.

Fixed exactly the same bug as before, but this time for incremental
sync. Yay tests!

- Test data for the sync server is now in its own file.
- Rejig the sync server tests to support multiple /sync requests and corresponding
  assertions.
- Fixed a minor bug which resulted in state events to appear twice in /sync
  responses when syncing without a `since` parameter.