[Nut-upsdev] Converting megatec_usb.c -> serial_usb.c

[Arjen de Korte]

Folks,

I think the present megatec_usb.c deserves to be renamed to
serial_usb.c. I think it potentially could serve many more UPS'es with
built-in USB-to-serial converters, not limited to the megatec_usb driver
(although that was the first one to use this). I also think a more
layered approach would be nice, in the same fashion as the usbhid-ups
driver with subdrivers. Which would mean that we would split-off the
lowlevel stuff (agiler, krauler) in separate source files and keep the
remainder in serial_usb.c. Ultimately, the goal would be to bundle
everything in a library that could be linked in by devices that have
this kind of interface. Any thoughts/objections from making this split?

Best regards, Arjen