it seems like most build systems pass a -DHAVE_CONFIG_H flag to the
compiler which still causes `#if HAVE_CONFIG_H` to be false while it
clearly is supposed to be triggered.
That said, I do not really see a good reason why the inclusion of the
`config.h` file should be guarded in the first place: the file is
guaranteed to always available by proper build systems, and if it was
not included the build either breaks at the linking stage or -- at the
very least -- the runtime behavior of the resulting libraries will be
very awkward.
i.e. it now supports stuff like MULTFLT in the schedule
section. Possibly, the MPI-parallel code paths need some fixes. (but
if the geology is not changed during the simulation, the parallel code
will do the same as before.)
the most fundamental change of this patch is that the
reference/pointer to the DerivedGeology object is made
non-constant. IMO that's okay, though, becase the geology can no
longer assumed to be constant over the whole simulation run.
to be able to determine the threshold pressure from the initial
condition it needs to be able to access the initial condition, i.e.,
the initial simulator state, material properties object and gravity
constant need to be passed to the thresholdPressure() function.
