Remove testget handler

used for debugging the bridge functions
minor comment and serial cleaning

very minor
Added trigger_LED and prepped reset_LED

Trigger LED goes on when sound module is triggered and goes off when
trigger sound has stopped playing.
Removed export handler --> handled in GUI

In the web GUI > export > right click on the settings.txt link and
program.txt link and save them. No need for extra cruft.
Attempting toggle logic + skeleton code for new duration modes

Extending the firmware outputSelectFunction to do 3 things:
on/off/toggle.