Cosserat-Continuum-Nonplanar

@osander: Can you have a look here?

This MR cleans up the usage of MIXED_SPACE in cosserat-continuum.

Now all combinations of dim = dimworld or dim != dimworld and MIXED_SPACE = 0 or MIXED_SPACE = 1 at least compile.

Also, this MR points out the one combination that still can't be solved: Problems with dim != dimworld do not work for MIXED_SPACE = 1!

As soon as I need this for locking tests I will add this; I will have to change Nonplanarcosseratshellenergy so it can be assembled with the GFEMixedAssembler.

dune/gfe/surfacecosseratstressassembler.hh

@@ -96,6 +96,7 @@ namespace Dune::GFE {
             // Compute gradients of Base functions
             for (size_t i=0; i<gradients.size(); ++i)
               gradients[i] = referenceGradients[i] * transpose(jacobianInverseTransposed);
+              //jacobianInverseTransposed.mv(referenceGradients[i][0], gradients[i]);
 
             // Deformation gradient in vector form
             size_t nDoubles = dim*dim;
@@ -248,6 +249,8 @@ namespace Dune::GFE {
               for (size_t i=0; i<gradients.size(); i++)
                 gradients[i] = referenceGradients[i] * transpose(jacobianInverseTransposed);
 
+                //jacobianInverseTransposed.mv(referenceGradients[i][0], gradients[i]);
+
               // Deformation gradient - call this U_es_minus_Id already
               FieldMatrix<double,dim,dim> U_es_minus_Id(0);
               for (size_t i=0; i<gradients.size(); i++)