Philippe 13/12/2018: split mode_netcdf module into multiple modules + add new subroutines to check if a file has been closed correctly
This is done:
*to reduce circular dependencies problems
*to have cleaner code
*to compile faster
*to detect problems with not correctly closed netCDF files

Philippe 05/12/2018: cdf2cdf: better support for older files (<5.4.0) and special treatment for EMIS

Philippe 27/11/2018: LFI2CDF: correct problems when reading files generated with older versions (tested on 5.3.1 files)

Philippe 10/04/2018: lfi2cdf: take into account previous commits on dimension variables + bug correction on NKMAX

* treat more correctly datetime variables from LFI files
* pass HPROGRAM_ORIG at closing and not opening of file

* improvements
* split option works again

Philippe 16/03/2018: lfi2cdf: remove file suffix from hinfile and houtfile to manage more cleanly filenames

Philippe 13/02/2018: IO_GUESS_DIMIDS_NC4: manage variables with CLBTYPE/=NONE + add a return value + problems are now WARNING instead of FATAL

* write NF90_INT1 instead of NF90_INT for logicals
* use IO_WRITE_FIELD (not yet done everywhere)
* if NTYPE is unknown => fatal error
* do not try to read JPVEXT (never written)

Philippe 09/03/2018: lfi2cdf: remove redundant fields of workfield (present also in TFIELDDATA) + remove read_data_lfi