Bugfix #2482 main_v11.0 time slicing yyyymmdd

[hsoh-u]

Expected Differences

The 8 digits number should be interpreted as yyyymmdd (converted to unixtime in seconds unit).

• Do these changes introduce new tools, command line arguments, or configuration file options? [No]
  
  If yes, please describe:
  

• 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:
  

This command does not work because $MET_TEST_INPUT (/d1/projects/MET/MET_test_data/unit_test) is not mounted at seneca.

/d1/personal/hsoh/git/pull_request/MET_bugfix_2482_timeslicing_yyyymmdd_main_v11.0/bin/plot_data_plane /d1/projects/MET/MET_test_data/unit_test/model_data/nccf/gtg/latlon/gtg_obs_forecast.20130730.i00.f00.nc plot.ps 'name="edr"; level="(20130730,0,*,*)";

Alternative test:
/d1/personal/hsoh/git/pull_request/MET_bugfix_2482_timeslicing_yyyymmdd_main_v11.0/bin/plot_data_plane /d1/projects/MET/MET_test_data/unit_test.sav/model_data/nccf/GloTEC_TEC_2015_03_17.nc tmp_test.ps 'name="TEC"; level="(20150317,,)"; file_type=NETCDF_NCCF;' -v 4

Before: "20150317" to 20150317

WARNING: MetNcCFDataFile::convert_time_to_offset() -> 20150317 does not exist at time variable

After: "20150317" to 1426550400

WARNING: MetNcCFDataFile::convert_time_to_offset() -> 1426550400 does not exist at time variable

date +%s -d "20150317" -u
1426550400

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

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

• Do these changes include sufficient testing updates? [Yes or No]

• Will this PR result in changes to the test suite? [Yes or No]
  
  If yes, describe the new output and/or changes to the existing output:
  

• Please complete this pull request review by [Fill in date].
  

Pull Request Checklist

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[JohnHalleyGotway]

I approve of these changes.

Please see this #2483 comment for details.