* For netcdf_c version 4.7 it's now mandatory to first include netcdf.h.

* This also allows for overrides at make invocation.

* When CXX=CC and FC=ftn are used simultaneously on a CCE 8.7 system,
  ftn inherits the output_verbose_link_cmd as postdeps from the C++
  tests and everything goes wrong afterwards even for non-shared
  archives.

* This was needed to get working builds on Piz Daint, libtool 2.4.2 generated
  bogus dependencies on libquadmath.so.

* Apparently craycc also makes some optimistic assumptions about the effect
  of comparing -0.0 to 0.0.

* For some reason gcc 9.1 does not detect that status is never used
  uninitialized.

* Given how many lines documenting the confusing pattern and how many
  compiler warnings are eliminated by this change...

* Port this upstream and turn it into a cgribexlib update.

* AM_CONDITIONAL must be defined in all control flows, or configure cannot
  finish successfully.

* There is no caller for the newly removed function stubs anyway.

* GCC 8.x and newer warn about the previously used "void (*)()", use
  "void (*)(void)" instead.