Saturation table scaling and hysteresis.

This commit implements some additional scaling keywords.  This includes
the ISWL-family that provide hysteresis behaviour via alternative
scaling of the tables.  The old parser has been somewhat extended for
testing purposes.  The commit also includes a slight refactoring of the
SatFunc-family where a new base class has been introduced.
RV is back in business.
RV is back in business - a second attempt.
Removed blanks from strings.
Merge pull request #478 from osae/endscale

Saturation table scaling and hysteresis.