Feature 1918 std climo

[JohnHalleyGotway]

Expected Differences

• Do these changes introduce new tools, command line arguments, or configuration file options? [Yes]
  
  If yes, please describe:
  

Adds "normalize" option to the Gen-Ens-Prod config file.

• Do these changes modify the structure of existing or add new output data types (e.g. statistic line types or NetCDF variables)? [No]
  
  If yes, please describe:
  

Pull Request Testing

• Describe testing already performed for these changes:
  
  Tested manually and also added a new call in unit_gen_ens_prod.xml to exercise all available options for the normalize config option.

• Recommend testing for the reviewer(s) to perform, including the location of input datasets, and any additional instructions:
  

• Review the code changes.

• Review the documentation updates in the gen_ens_prod chapter.

• Inspect the new unit test gen_ens_prod NetCDF output file to make sure the outputs look good.

• Consider this design choice:

  • For normalize = FCST_STD_ANOM, we subtract the ensemble mean and divide by the spread. If a control member is specific, it is excluded from the computation of the spread... because that's how it's handled more generally in gen_ens_prod and ensemble_stat.

• Test this feature branch manually using your own test data in:
  seneca:/d1/projects/MET/MET_pull_requests/met-10.1.0/met-10.1.0-beta6/feature_1918/MET-feature_1918_std_climo_into_develop/met/bin

• Do these changes include sufficient documentation updates, ensuring that no errors or warnings exist in the build of the documentation? [Yes]

• Do these changes include sufficient testing updates? [Yes]

• Will this PR result in changes to the test suite? [Yes]
  
  If yes, describe the new output and/or changes to the existing output:
  
  New output file named gen_ens_prod/gen_ens_prod_NORMALIZE.nc is created. That is the only difference flagged in the GitHub actions for this PR:

ERROR: folder /data/output/met_test_truth missing 1 files
    gen_ens_prod/gen_ens_prod_NORMALIZE.nc 

• Please complete this pull request review by [Tues 2/22/2022].
  

Pull Request Checklist

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[JohnHalleyGotway]

@j-opatz do you have updated requirements to share on this PR? Based on our discussion from this morning, should I remove the FCST_ANOM and FCST_STD_ANOM options from Gen-Ens-Prod? Honestly, that'd be more efficient anyway. Using them requires the tool to read the same data twice... once to compute the mean/spread and once to use that computed mean/spread to normalize each member.

[j-opatz]

Documentation for the changes looks good, and updates to code still solve the problem in the original issue, with a slight change in approach (now includes series-analysis). Automated testing shows no issues, and code updates appear sound, both reading and during usage.