Makes distinction between functions more clear.

Currently, there are two abstract interface for the grids. One that
usually returns pods and arrays of them that also can be used by C
and is used also in opm-core, and one that returns Eigen datastructures
 needed within opm-autodiff.

This commit adds a postfix ToEigen to those functions (faceCells, and
cellCentroidsZ) one could imagine to also return pods and arrays of them.
This should at least resolve the confusion about the two faceCells functions.

The next step will be issue #192
Fixes #176
Add output of RS and RV to outputStateMatlab
Merge pull request #195 from totto82/rs_rv_output

Add output of RS and RV to outputStateMatlab
Apply threshold pressure for all dp
The threshold pressure is applied for all dp.
The sign of the threshold pressure is given by the sign of the dp.
sim_fibo_ad*: change the default for the use_cpr parameter from false to true

SPE9 and Norne are basically unusable if UMFPack is used as linear solver...
Merge pull request #197 from andlaus/use_cpr

sim_fibo_ad*: change the default for the use_cpr parameter from false to...
Merge pull request #193 from blattms/fix-176

Makes distinction between functions more clear. (#176)
Merge pull request #196 from totto82/bugfix_thpress

Apply threshold pressure for all dp
enabled DUNE-ISTL::AMG and DUNE-ISTL::CGSolver.
The default is the same as before, i.e. DUNE-ISTL::ILU0 and DUNE-ISTL::BiCGSolver
for solving the elliptic problem.
Calculate oil saturation from changes in water and gas saturation
First the change in oil saturation is calculated from changes in water
and oil saturation. Then oil saturation is updated based on this change
instead of just fixed to 1-sw-sg. With this change the oil saturation is
less sensitive towards numerical errors that may cause very small oil
saturations. Witch again may cause the simulator to think that the gas
phase is saturation with vaporized oil when it is not.
Add comments and change order for readability.
Merge pull request #200 from totto82/fix_updateState2

Update oil saturation from changes in water and gas saturations
Fix out-of-bounds indexing into PVT function table

The 'props_' table of PVT functions has one entry for each active
phase.  Fix four instances of indexing into the table using the
canonical rather than active phase indices.

This is necessary, but not sufficient, to run two-phase problems
without a "dummy" third phase.
Merge remote-tracking branch 'upstream/master'
apply nitpicks comments and avoid delete.
adapt the the table related API changes of opm-parser
Merge pull request #199 from dr-robertk/master

enabled DUNE-ISTL::AMG and DUNE-ISTL::CGSolver in CPRPreconditioner.
Merge pull request #203 from andlaus/table_improvements

dapt the the table related API changes of opm-parser
Merge pull request #204 from bska/fix-oob-pix

Fix out-of-bounds indexing into PVT function table
Remove header generation, add define for warning suppression.

Thanks to @akva2 for original patch.