Use `isOnline` from libquotient This require a bump of the min libquotient to 0.9.1
To make this work `AccountManager` is split off from controller taking all the code around `AccountRegister` and is added to LibNeoChat as it makes sense to have this functionality there.
Move `NeoChatConnection` and `NeoChatRoom` to `LibNeoChat` along with any required dependencies.
