Tuxwave fixups

Have made some changes to tlf:

-Use a S&P Callsign, so that possibly the speed of it can be controlled with +  and -

(I needed the feature of the S&P Callsign because the last time i used
tlf (the first one time also), i used a optocoupler attached to the
serial port. Also i was working at DB0RC, which callsign often got
confused with DD0RC, so i needed so put some String, like D--B++0RC, to
make the B better audible.)

-This callsign is also being used with the message key
-Added ? functionality to send incomplete (or even complete) callsigns appended with ?

Needed is:

Add S&P_CW_CALL in the rule files
Check ph_message[4] is valid (should be a sound file requesting for the callsign)