[modelTraits] include UseMole and ReplaceCompEqIdx in model traits

Closes #501

See merge request !1046

make initial solution impl compatible with enriched schemes

See merge request !1051

If enriched vertex mappers are used (multiple dofs at vertex), the
initial function requires the mapper to provide index maps of the form
mapper.index(entity). However, direct mapping from vertices to dofs is
not possible because it is not unique. This implementation works for
both cases.

Feature/porosity deformation law

See merge request !1026

After using the new porosity law, this is overhead for output purposes
at the moment. If this output is desired it can be added manually.

Freeflow/renaming

See merge request !1050

Freeflow/wallfunctions for ncni

See merge request !1047

Fix/grid includes

See merge request !1042

[cornerpoints] Change the cornerpoint grid creator into a grid manager

See merge request !1043

Freeflow/kepsilon wallfunction rebased

See merge request !1040

[test][tutorial] Make executables compile again

See merge request !1041

reference result change, but fine solution is still good

Then a lower y^+-value can be chosen

Feature/remove grid singleton

Closes #431

See merge request !1037

Implement a grid manager class that creates grids and a grid data object. The new class
is no longer a singleton. It is instantiated by the user. It is possible to get a
shared_ptr to the grid data to pass it on to e.g. problem / spatial parameter classes.

* No longer sets the overlap automatically (overlap to be checked by the grid geometry)
* Does not depend on discretization method or TypeTag anymore

Joint work with Kilian Weishaupt <kilian.weishaupt@iws.uni-stuttgart.de>