Bug 30237: Control port module improvements for v3 client authentication

Split the configuration portion of the controller() function into
a new configureControlPortModule() function. This allows the
Torbutton code to continue to own the configuration (with help from
Tor Launcher) while making it possible for the v3 client authentication
prompt to use Torbutton's control port module.

Also, include error information returned by Tor within error objects
generated by the control port module and add support for Tor's new
ONION_CLIENT_AUTH_ADD control port command.