first handle all integer properties, then all double ones

this is required in situations where double grid properties depend on
the values of integer (i.e, *NUM) ones which appear later in the
deck. Example:

```
PROPS

SWU
* /

REGIONS

SATNUM
*2 /
```

the default value of the SWU keyword depends on the value of the
SATNUM property which only gets defined later in the deck. an
alternative to the approach of this patch would be to process the
grid properties of the REGIONS section before the others. I'm a bit
indifferent which approach is better...
Merge pull request #294 from andlaus/GridProperties_first_int_then_double

first handle all integer properties, then all double ones
fix compiler warnings and rename CF to ConnectionTransmissibilityFactor

for the compiler warnings, see e.g.

https://opm-project.org/CDash/viewBuildError.php?type=1&buildid=27777

the CF to ConnectionTransmissibilityFactor rename makes things much easier to
understand for people who are not intimately familiar with the wells
code.
Merge pull request #300 from andlaus/fix_warnings

fix compiler warnings and rename CF to CompletionFactor
EclipseState: provide an accessor method for the unit system used by the deck

this is required to convert calculated quantities to the same units as
the ones used in the input deck.
Merge pull request #301 from andlaus/EclipseState_export_unit_system

EclipseState: provide an accessor method for the unit system used by the deck
Fixed dimension of Kh item to Permeability*Length