Replaced IV_gage_id by IV_gagetot_id and IV_gageuse_id
Cleaned up read only, changed Fortran unit for basin_id_file
Replaced IV_gage_id by IV_gagetot_id and IV_gageuse_id. Changed Fortran unit for basin_id_file and gagetot_id_file. Added gageuse_id_file
Fixed bug with minor influence on results of David et al. (2011, HP): ZV_read_gagetot was used instead of ZV_read_forcingtot when forcing