Allow run_set creation with non-standard forcing file names

[awlostowski-noaa]

The implicit run_set creation capability is currently customized to work with forcing files (channel route out files) of a standard naming convention: YYYYMMDDHHMM.CHRTOUT_DOMAIN1. This pull request modifies nnu.build_forcing_sets such that the set creation processes works with other filenames that may not contain 12-digit date codes, or when globbed and sorted, may not necessarily be in chronological simulation order.

At the root of this change is a new (optional) user input parameter named is_date_in_forcing_filename (logical). This parameter is only required if implicit run set creation is requested (along the V3 execution pathway).

• If is_date_in_forcing_filename == True, then the forcing filenames with a 12-digit datetime code are expected to appear somewhere in forcing filenames (specifically, YYYYMMDDHHMM).
• If is_date_in_forcing_filename == False, then no assumptions are made about filenames and we do not expect a globbed and sorted forcing file list to necessarily be in chronological simulation order. The simulation datetimes of each forcing file in the forcing directory are directly observed by evaluating the NetCDF file attribute, model_output_valid_time
• If not specified, then is_date_in_forcing_filename defaults to True

[awlostowski-noaa]

Testing

conventional forcing filenames, is_date_in_forcing_filename == True:

[{'qlat_files': [
'201809080100.CHRTOUT_DOMAIN1', '201809080200.CHRTOUT_DOMAIN1', '201809080300.CHRTOUT_DOMAIN1', 
'201809080400.CHRTOUT_DOMAIN1', '201809080500.CHRTOUT_DOMAIN1', '201809080600.CHRTOUT_DOMAIN1', 
'201809080700.CHRTOUT_DOMAIN1', '201809080800.CHRTOUT_DOMAIN1', '201809080900.CHRTOUT_DOMAIN1',
'201809081000.CHRTOUT_DOMAIN1', '201809081100.CHRTOUT_DOMAIN1', '201809081200.CHRTOUT_DOMAIN1'
], 
'nts': 144, 'final_timestamp': datetime.datetime(2018, 9, 8, 12, 0)}]

• The same results is obtained if is_date_in_forcing_filename == False, thought it takes longer.

(UN)conventional forcing filenames, is_date_in_forcing_filename == False:

[{'qlat_files': [
'nwm.t16z.analysis_assim_extend.channel_rt.tm27.conus.nc', 'nwm.t16z.analysis_assim_extend.channel_rt.tm26.conus.nc',
'nwm.t16z.analysis_assim_extend.channel_rt.tm25.conus.nc', 'nwm.t16z.analysis_assim_extend.channel_rt.tm24.conus.nc',
'nwm.t16z.analysis_assim_extend.channel_rt.tm23.conus.nc', 'nwm.t16z.analysis_assim_extend.channel_rt.tm22.conus.nc',
'nwm.t16z.analysis_assim_extend.channel_rt.tm21.conus.nc', 'nwm.t16z.analysis_assim_extend.channel_rt.tm20.conus.nc',
'nwm.t16z.analysis_assim_extend.channel_rt.tm19.conus.nc', 'nwm.t16z.analysis_assim_extend.channel_rt.tm18.conus.nc',
'nwm.t16z.analysis_assim_extend.channel_rt.tm17.conus.nc', 'nwm.t16z.analysis_assim_extend.channel_rt.tm16.conus.nc'
],
'nts': 144, 'final_timestamp': datetime.datetime(2021, 10, 21, 0, 0)}]