Remove initialization from data structure.
Replace the previous virtual_init() with a virtual_init() that initializes the
data structures to a default state
Create virtual_sync() function to push the state of virtual devices to the
physical outputs. Moved from the previous virtual_init() function.
The virtual device table is now built by direct calls to virtual_add() from the
setup function.
Toward issue [#23]
Clean compile of asdf_keymaps.c/h and tests
Clean up keymap pointer notation
Reduce number of keymaps to 16, matching number of DIP switches allocated for
keymap selection.
(WARNING: WIP) Gathered Work-in-progress on alternate keymap defs
Exploratory branch. Code is messy and untested.
Examining creating a module for each keymap rather than header file.
