downloads binary fix files from an EMC FTP site where it is version controlled manually. Per @ShelleyMelchior-NOAA, these binary fix files do not change in years.
add a shell script ush/download_fix.sh to manually download binary fix files if necessary.
The downloaded files are checked for exact chksum. This serves as a poor man's version control.
This PR:
ush/download_fix.shto manually download binary fix files if necessary.chksum. This serves as a poor man's version control.