Modify precision for quadrature depending on use of CVI method.
Scaling of relperm functions - oil/water systems.

opm/core/eclipse/EclipseGridParser.cpp
opm/core/eclipse/EclipseGridParser.hpp
- New keywords: ENDSCALE SCALECRS SWCR SWL SWU SOWCR KRW KRWR KRO KRORW

opm/core/eclipse/SpecialEclipseFields.hpp
- Parsers for ENDSCALE and SCALECRS.

opm/core/fluid/BlackoilPropertiesFromDeck.cpp
- Consistency check: ENDSCALE implemented for SatFuncSimple only.

opm/core/fluid/SatFuncGwseg.hpp
opm/core/fluid/SatFuncSimple.hpp
opm/core/fluid/SatFuncStone2.hpp
- Accomodate "default" values for scalable parameters.
- For SatFuncGwseg and SatFuncStone2 the associated functionality not
  yet supported and the variables are dummies to satisfy the compiler.

opm/core/fluid/SatFuncSimple.cpp
- Initialisation for scalable parameters.
- Evaluation of relperms: Use (1-so) for evaluation of oil-relperms.
  (For scaled arguments sw and so do not necessarily add to one.)
- TODO: SatFuncGwseg.cpp and SatFuncStone2.cpp for oil-water systems.

opm/core/fluid/SaturationPropsFromDeck.hpp
- Struct to accomodate cell-wise scaling factors.
- Two flags indicating scaling and method.
- Methods for parameter initialisation and scaled relperm computation.

opm/core/fluid/SaturationPropsFromDeck_impl.hpp
- Initialize scaling options and relevant cell-wise scaling factors.
- Relperm evaluation modified for possible end point scaling.
Removed tabs.
Fixed loop index and added parameter check.
Implemented 2d quadrature rules for degree 1 and 2 (order 2 and 3).

Also added cartesian 2d cell testcase.
Bugfix: multiply by edge length in 2d face quadrature weights.
Ensure correct output in case of Lapack error.

Make sure that we output the original values, since Lapack may overwrite those
used in the call.
Loop index.
Support for keywords ENPTVD and ENKRVD.
Bugfix: use sufficient quadrature order.
Added limiter for DG1, parameter 'use_limiter'.

The limiter is experimental and unfinished, untested work in progress.
Limiter is therefore inactive by default.

Also fixed a minor bug: use_cvi_ was not initialized.
Merge pull request #103 from osae/endscale

Scaling of relperm functions - oil/water systems.
Merge pull request #109 from atgeirr/dg-improvements

DG time-of-flight improvements
Limiter now works reasonably well.

Case with no inflow faces should be checked.
Added solveTofTracer() method.
Added parameter compute_tracer. Defaults to false.

Triggers tracer computation and output, in addition to time-of-flight.
Merge pull request #110 from atgeirr/dg-improvements

Improvements for time-of-flight and tracer computations
Bugfix: take minimum of allowed slopes, not maximum.
Bugfix, again: it was correct to take the maximum, reinstating.

There is a different problem that needs fixing, however:
Flux inaccuracies (for example on boundaries) may tag some
face as inflow face for a cell, even if it should have been
no-flow. This may let the cell avoid limiting, even though it
should have been limited according to the proper inflow faces.
Simplify and correct implementation of limiter.

Now we check all corners' tof values for the cell under consideration,
not just the inflow face corners'.