Modifications of the covers files for ECOCLIMAP

The mode_cover files are replaced by some ASC/BIN files ( ecoclimapI_covers_param.bin/dat, ecoclimapII_eu_covers_param.bin/dat, ecoclimapII_af_covers_param.bin/dat), with a little program to convert data from one format to the other, convert_ecoclimap_param.f90.

These files are present in directory MY_RUN/ECOCLIMAP.

Possible modifications can be done in the ASC files, then the f90 program has to be adapted to read these ASC modified files.

And the Surfex subroutine that reads theses files too: read_covers_param.F90.