(cherry picked from commit f06a12ec)

Philippe 15/10/2020: IO: Write_les_budget_n: restructure Les_diachro calls to use tfield_metadata_base type

Philippe 15/10/2020: IO: Write_les_rt_budget_n: restructure Les_diachro calls to use tfield_metadata_base type

Philippe 14/10/2020: IO: Write_les_sv_budget_n: restructure Les_diachro calls to use tfield_metadata_base type

Philippe 09/10/2020: IO: bugfix: NF90_GET_ATT was called by all processes and not by only the readers

Philippe 08/10/2020: IO: add new dimensions in diachronic files + their treatment in IO_Vdims_fill_nc4

(cherry picked from commit dacdd3fe)

Philippe 30/09/2020: IO: add IO_Field_write_box_byfield_X3 subroutine (used in future version of Write_diachro)

Philippe 22/09/2020: IO: add ldimreduced field to allow reduction in the number of dimensions of fields (used by 2D simulations)
+ adapt ndimlist

(cherry picked from commit 88b2d19b)
(cherry picked from commit d88b6203)

Philippe 22/09/2020: safety check: do not execute block of codes for L2D+LPACK=true in parallel (incomplete implementation)