missing length counter update call for wave channel

broke street fighter 2

two accuracy fixes:

- length counter should be updated immediately on write, not during
  channel trigger.
- zombie mode volume swap only occurs if the volume envelope direction
  changed.

More tweaks to new -dd debug mode.

New test ALSA impl w/poll. Add goto key + conffile

Goto track key is return/enter.
Config file currently only used to persist the volume.
  It's located at $XDG_CONFIG_HOME/minigbsrc
  (or ~/.config/minigbsrc if XDG_CONFIG_HOME is unset).

Wave channel improvement + note display fix.

Wave channel wasn't always setting the sample properly, it should now be
less whiny. Kirby's dream land track 1 is a good test.

Fixed note display sticking if the track used a 0 volume write
(DAC disable) to cut notes. (e.g. Ottifanten Kommando Stőrtebeker)

Quick fix for noise channel divide-by-zero

add support for files using tma/tac timing