allsky.sh: bug fix with ON_TTY plus reset_usb
allsky.sh: bug fix with ON_TTY plus reset_usb

Had a bug with $ON_TTY.
Check for capture exit code of 99 which means allsky.sh should attempt to reset the USB bus if possible to help eliminate ASI_ERROR_TIMEOUTs.
thomasjacquin/allsky,thomasjacquin/allsky,thomasjacquin/allsky