With tests to assert behaviour. Not hooked up yet. Stub datastore methods
not implemented yet.

Add stub ApplicationServiceTransactionStore. Bootstrap Recoverers. Fill in stub Transaction functions.

Evolution of push rules

Add more server default rules so we have default rules for whether you get notifs for invites / random member events

Don't look for a TLS private key if we have set --no-tls

Add some randomness to the user specified timeout on event streams to mi...

Add the highlight tweak where messages should be highlighted a different colour in appropriate clients.

Add some randomness to the user specified timeout on event streams to mitigate against thundering herds problems

Handle if get_missing_pdu returns 400 or not all events.