it now uses the grid object which gets created by ebos for everything
which should make the parallelization efforts easier. I also tried to
cut back the use of the legacy property objects (i.e., for the fluid,
geologic and rock properties), but this effort ran aground because of
the initialization and output code. (also, if those two were fixed,
there would probably be issues with the Newton update.)
I ran Norne with this and there did not seem to be any notable
performance regressions or benefits.
