Starts a new connection based on the passed SessionConfig.
Issuing a connection with an already existing connected resource will just
replace the existing connection (disconnecting the old) with another.
A disconnect + connect event will occur in that case.
They are unique by type T.
Promotes one of the clients to a host
All the other participants will then become clients to this new host.
The session is considered unaltered, the uuids will be staying the same.
The Channel::host_uuid will return the new host as the uuid once the
process is complete.