Accessory Decoder Beta 1.0 Firmware

Here is a first blast of the accessory decoder firmware. It is really just an alpha for real enthusiasts since it is not very NMRA compliant and not very feature rich. User IDs are D003 and CV7 reads as 4
 
It will work in a 12F629, 12F675, 16F630 or 16F676 (the same as the function decoder firmware) and uses the same circuit as the function decoder.
 
It supports output address mode or decoder address mode (configured in CV29), can be configured for 'momentary mode' (CV33=0) or 'Lenz toggle mode' (CV33=15) and supports all normal addresses in CV1 and CV9.
There is no support for 'output on time' yet.
