New tone_alarm driver, now features GWBasic PLAY / ANSI music string format
Add support for arbitrary user tunes on the commandline.
Add one more tune. Improve error handling. Be less picky about tunes passed on the command-line.
One more tune. Might be a bit big to keep.
more constness
Fix a typo in several of the basic alarm beep tones.
Adjust audio pattern numbers.
Silence the tone for pauses in legato tunes. Some tunes sound better now.

Add new, distinctive error/notification tones.

Reduce the amount of data space consumed by the largest tune.
Merge pull request #220 from PX4/tone_alarm_PLAY

New tone_alarm driver that uses ANSI music / GWBasic PLAY strings