Very minor enhancements.
Reordered some configuration files.The BOARD_VERSION macro has been removed. Instead the version is now encoded in the other BOARD_XXX macros.
Changed all header guards so they will not use unserscores as pre- and postfix.
updated all file headers to 2019
Added some basics to mask pads during GPIO initialization (wip)
Doxygen file documentation and modules.
Introduced SSSP stage 3 of the startup phase (module stack initialization).
moved the /os/modles directory to /modules