[operators.interface] removed 'range = apply(source)'
[operators.eigen] fixed EigenDenseMatrix
[test.operators] update
[parameters.base] added some docu
[functions.interfaces] some fixes
[functions.default] make it work
[test.functions] update
[functions.interface] added constructor
to forward parameter construction
[functions.interfaces] made virtual functions virtual
[parameters.base] removed protected parameter_type() from Parametric
[functions.default] renamed ParametricDefault -> NonparametricWrapper
[functions.default] added NonparametricExpression
[functions.default] finished AffineParametricDefault
[test.functions] added NonparametricExpressionTest
and AffineParametricDefaultTest