Changes for version 1.2
- update sndlib/config.guess and config.sub, recreated configure.
- birds now uses PGPLOT only when USE_PGPLOT=1 is set in the environment.
- created and installed bin/pdlaudio-demo and pdlaudio-birds.
- make clean makes clean in sndlib as well.
- embellished the intiial gen_oscill example a bit.
All the standard musical pitch names.
Over 1200 musical scales in PDL format.