LinTrain Code

Enhancements to CDU decoder PIC code:
- Changed resolution of output duration to 10ms
- Duration with top bit set now means the channel is a slave of the one before
- Now uses CV545 (bottom 3 bits) to adjust the boost voltage

Clean out an unwanted file - legacy of CVS

Modified CDU turnout decoder hardware to use parts from the JLCPCB SMD stock

Updated the "light accessory" decoder design to use a more modern PIC in SMD

Updated optical detector design to use a more modern PIC
Ported code to the new device and a nicer build system

Small adjustments to the CDU turnout decoder hardware design.

Updated GUI scripts to Python 3

Created a new, standalone command station using an STM32 ARM CPU

Updated web page with new release info

Removed a bunch of inappropriate "executable" tags from non-trunk paths