[speechd-el] Please make path to Speech Dispatcher socket configurable

[Alain Kalker]

Hi list, Milan.

Currently, speechd-el hardcodes the path to the Speech Dispatcher socket 
to be "~/.speech-dispatcher/speechd.sock . However, Speech Dispatcher, 
like many modern applications, creates its directory with run-time data 
in $XDG_RUNTIME_DIR , so the socket is actually created in 
"$XDG_RUNTIME_DIR/speech-dispatcher/speechd.sock" .

Also, currently the path to this socket is not customizable, unlike many 
other settings like SSIP hostname and port, etc.

Please update the path to the socket to this more modern convention 
annd/or make it customizable.

Kind regards,

Alain Kalker