RT1***LocalFiniteElement returns wrong values

Unit-testing the classes RT1Cube2DLocalFiniteElement and RT12DLocalFiniteElement uncovered run-time / wrong-result bugs in both of them: (MR !127 (merged))

Bug in LocalInterpolation for finite element type Dune::RT1Cube2DLocalFiniteElement<double, double> const
    Degree of freedom 0 applied to shape function 0 yields value 0, not the expected value 1

Bug in LocalInterpolation for finite element type Dune::LocalFiniteElementVirtualImp<Dune::RT1Cube2DLocalFiniteElement<double, double> > const
Degree of freedom 0 applied to shape function 0 yields value 0, not the expected value 1

testFE(rt1cube2dlfemDedicated) failed
Bug in LocalInterpolation for finite element type Dune::RT12DLocalFiniteElement<double, double> const
    Degree of freedom 0 applied to shape function 0 yields value 0, not the expected value 1

Bug in LocalInterpolation for finite element type Dune::LocalFiniteElementVirtualImp<Dune::RT12DLocalFiniteElement<double, double> > const
Degree of freedom 0 applied to shape function 0 yields value 0, not the expected value 1

testFE(rt12dlfemDedicated) failed

That's quite dangerous: You may not even notice that your RT problems are assembled incorrectly.

@gruenich , didn't you write those? Could you have a look?