pieusb_usb: report unknown scsi status as error
pieusb: add pieusb_wait_ready()
pieusb_buffer: check status of create_buffer
pieusb_scancmd: cmdGetScanParameters -> pieusb_cmd_get_parameters
pieusb_scancmd: improve get_state debug
pieusb_specific: use pieusb_wait_ready as wait loop
pieusb_buffer: fix state return from create_buffer
pieusb_usb: define SEQUENCE_LEN
pieusb_specific: handle TYPE_GROUP in print_options
cmdSetScanFrame -> pieusb_cmd_set_scan_frame
pieusb_scancmd: rename cmd{G,S}etRelativeExposureTime, cmd{G,S}etHighlightShadow