restore the hydrostatic equilibration test from opm-core

This involved quite a bit of kicking and screaming. The result
certainly is not pretty, but it works.

tests/equil_capillary.DATA

@@ -0,0 +1,87 @@
+-- Most of the following sections are not actually needed by the test,
+-- but it is required by the Eclipse reference manual that they are
+-- present. Also, the higher level opm-parser classes
+-- (i.e. Opm::EclipseState et al.) assume that they are present.
+
+-------------------------------------
+RUNSPEC
+
+WATER
+OIL
+GAS
+
+DIMENS
+1 1 20 /
+
+TABDIMS
+  1    1   40   20    1   20  /
+  
+EQLDIMS
+-- NTEQUL
+     1 /
+
+-------------------------------------
+GRID
+
+-- Opm::EclipseState assumes that _some_ grid gets defined, so let's
+-- specify a fake one...
+
+DXV
+1*1 /
+
+DYV
+1*1 /
+
+DZV
+20*5 /
+
+DEPTHZ
+4*0.0 /
+
+PORO
+   	20*0.3 /
+
+PERMX
+	20*500 /
+
+-------------------------------------
+PROPS
+
+PVDO
+100 1.0 1.0
+200 0.9 1.0
+/
+
+PVDG
+100 0.010 0.1
+200 0.005 0.2
+/
+
+PVTW
+1.0 1.0 4.0E-5 0.96 0.0
+/
+
+SWOF
+0.2 0 1 0.4
+1   1 0 0.1
+/
+
+SGOF
+0   0 1 0.2
+0.8 1 0 0.5
+/
+
+DENSITY
+700 1000 1
+/
+
+-------------------------------------
+SOLUTION
+
+EQUIL
+50 150 50 0.25 20 0.35 1* 1* 0
+/
+
+-------------------------------------
+SCHEDULE
+-- empty section