Introduce applogfail* macros
bfg_strerror: Support for Windows system errors
ucs2tochar{,_dup} functions to convert USB string descriptors to char* format
Windows SetupAPI-based detection for USB VCOM devices (tested with CP210x and CDC)
Check for Windows DDK headers, and where they are (and build without them if unavailable)
Windows autodetect: clear detectone meta info
Merge branch 'win_autoscan' into bfgminer