Importing with gdal should allow selecting bands

[Dimitar Misev]

The variables format parameter allows to specify the bands or variables to be imported from an input file (​docs)

  // Specify variable names, band ids (0-based), etc.
  "variables": [ "var1", "var2", ... ],

But wcst_import.sh currently does not support selecting a subset of bands (although it does support for grib or netcdf).