Merge branch 'master' into develop

Merge branch 'master' into develop

This merge brings changes from the v4.2 release into the develop branch.
It also connects the v4.2 tag to future development on the develop branch.

* master:
  Fix scaling of negative starting latitude for Gaussian grids in g2print
  Add configuration stanza for PGI compilers on Linux/POWER9
  Add -qufmt=be to FFLAGS and F77FLAGS for XL/POWER/Linux configuration stanza
  Fix inconsistent kind types of arguments to MIN/MAX in module_map_utils
  Add missing category 21 for landmask calculation with modis_15s_lake land use
  Fix scaling of starting latitude in GRIB2 datasets on a Gaussian grid
  Initialize arrays in calc_ecmwf_p to avoid potential error in GHT calculation
  Update version number to 4.2