enable CDash

the most fun part of this was to find out that `include(CTest)` was
missing in CMakeLists.txt. The dropsite is

http://www.opm-project.org/CDash/index.php?project=opm-parser
Support 'SOIL' keyword

This commit introduces support for the SOIL (initial oil saturation)
keyword.  This is similar to existing keywords 'SWAT' and 'SGAS' and
needed to input some decks.
Merge pull request #220 from bska/support-SOIL

Support 'SOIL' keyword
Changed name of oil compressibility item.
Merge pull request #222 from joakim-hove/fix-PVCDO

Changed name of oil compressibility item.
Merge pull request #219 from andlaus/cdash_enablement

enable CDash
Changed name of items in PVCDO keyword.
Merge pull request #225 from joakim-hove/fix-PVCDO

Changed name of items in PVCDO keyword.
Fixed typo in item name
fix spurious GCC warnings

The root cause are pretty (too?) strict flags w.r.t. compiler
warnings. In this case, the offenders are "-Wmissing-declarations" and
"-Wtype-limits".
Merge pull request #227 from andlaus/fix_gcc_warnings

fix spurious GCC warnings
Added Box() class to book keep the indices in a box.
Added constructor for sub box.
Added Box::equal() comparison function.
Added BoxManager() to keep track of the currently active input box.
ERT-656: Changed GridProperty to take (nx,ny,nz) instead of volume.
Basic BOX support when reading integer properties.
Added iterators begin() and end() to DeckKeyword class.
Added copyFrom() property to GridProperty
EclipseState now handles COPY keyword.