modify USB communications * use different data types for commands and responses * use variable length responses * maintain client/flasher compatibility with old format (e.g. when using old bootloader) * maintain bootloader compatibility with old format (e.g. when using old or RRG flasher.exe) * fix length of version string in appmain.c
usb communication (device side) refactoring * merge cmd.c into usb_cdc.c * move back usb_cdc.[ch] to common/ * declare low level functions usb_read() and usb_write() and more functions as static * use cmd_receive() in bootrom.c and appmain.c * remove unused memory wasting csrTab[100] in usb_cdc.c * replace more byte_t by uint8_t * more whitespace fixes