Update rooms and members on startup

[Cadair]

On startup of we should iterate over all the rooms in the database and query their state, things like names, members, if the rooms still exists etc.

This will probably need some extra service side hooks.

[networkjanitor]

Wouldn't it be better to have a session/run-scoped database and then adding rooms that you receive events from/for to it on the fly ? Meaning the error at

python-appservice-framework/appservice_framework/appservice.py

Line 249 in 4a213b5

log.error("message received with no matching room in the database")

would have to go and be replaced by a silent room create.

[Cadair]

I think the database should be persistent across runs, much as it is now, because otherwise after a restart the appservice would not know what to do with a message that arrived on the matrix side. The original point of this issue was basically validate the stored cache. Adding an optional mode where the room and non-auth user tables are blown away on startup could be useful.

As for the silent room creation, I think for things like the hangouts bridge, or something like the matrix IRC bridge that's definitely true, so it would be good to support it. I would have to give some thought to how we would want this to work in the case of a bridge where you invite a bot to a room on the service side.

fwiw, in the hangouts bridge I automatically create the room on service message before forwarding the message through the framework anyway. (So adding that feature to the framework would be useful)