GEOS-ESM/MAPL: MAPL 2.8.0.1

Changes to make MAPL 2 History output match GEOS FP file spec Coordinate Variables lon and lat are now 64-bit (double) in lat-lon History files rather than 32-bit (single) lons, lats, corner_lons, and corner_lats are now 64-bit (double) in History files rather than 32-bit (single) time is now an integer if the History is output at a frequency that is not a fraction of the time unit Variable Metadata Added fmissing_value (equal to _FillValue aka MAPL_UNDEF) Added missing_value (equal to _FillValue aka MAPL_UNDEF) Added vmin (equal to -MAPL_UNDEF) Added vmax (equal to +MAPL_UNDEF) Added add_offset (equal to 0.0) Added scale_factor (equal to 1.0) Added standard_name (equal to long_name) Global Metadata Added Title, History, Source, Contact, Convention, Institution, References, Filename, Comment These currently have hardcoded values roughly equivalent to the GEOS FP 5.27 output Full Changelog: https://github.com/GEOS-ESM/MAPL/compare/v2.8.0...v2.8.0.