Enhancement of wafs processing component

[YaliMao-NOAA]

To solve GTG crash issue because of extreme strong wind and make GFS post continue even in case of WAFS failure:

1. modify the GTG source code: when there is a high wind (>500 m/s), send out a warning WITHOUT error message
   and let the computation continue.
2. modify the script so the WAFS failure will not affect generation of GFS pgb file generation.

[YaliMao-NOAA]

I did two types of tests for this PR.

1. Submit a job with different task numbers, both results are bit-wise identical to each other.
2. To test the script change, I purposely copied the current operational ncep_post executable file to my local working directory and ran the same case with extreme strong winds. err=134 showed up as expected but didn't crash the entire job.

[WenMeng-NOAA]

Wen conducted the UPP standalone test on WCOSS-Dell. The fix can solved the wfas failure issue and has no impact on other GFS product generation. This PR is ready for merging.