enough of a start to break things, but not fix things; so it is a feature branch
Update of Test P to match current version of manuscript and current version of Darcy flux relation with 'k'.  The issue that Test P uses an unrealistically low conductivity of ~10^-6 remains; compare k=0.01 in Schoof/Hewitt work.  Fixes regression test for Test P.
Merge branch 'dev' into hydro-fix-k