jsonrpc_session_connect() indirectly called reconnect_disconnected(), which
told the reconnect object that the connection had failed, before it told it
that the connection attempt had started. When the connection didn't
complete immediately, this caused the connection to time out immediately,
without any backoff.
Reported by Jeremy Stribling.
SSL, which will be added in an upcoming commit, requires some background
processing, which is best done in a "run" function in our architecture.
This commit adds stream_run() and stream_run_wait() and calls to them from
the places where they will be required.
