gridinfo.hh: Use `subEntities(codim)` method instead of removed `count<codim>()` template method

See merge request !157

The `count<codim>()` template method was removed from the `Entity` facade class in
0cfc8f31

Cleanup UGGrid code

See merge request !156

The implementation is identical for both level and leaf intersections.

The `WorldVector` and `FaceVector` typedefs are already used in some
method declarations and in the implementation.  This patch uses them
consistently everywhere.

[bugfix] avoid subscript operator on JacobianTransposed

See merge request !154

A geometry's JacobianTransposed implementation may be any type modelling a
linear mapping, i.e., implementing the mv-type methods. Some grids
(e.g., SPGrid) only implement this interface for performance reasons.
However, we require that a JacobianTransposed can be assigned to a
FieldMatrix.

This patch fixes "checkCodim1Mapping" such that it will cast the
JacobianTranposed down to a FieldMatrix before accessing the subscript
operator (although the same result could be achieved using "mv").

UGGrid: append to-be-visited sons at the end of the list

Closes #53

See merge request !150

Handle unused boundary nodes correctly

Closes #55

See merge request !152

For "unused" boundary nodes the special value `-1` is used.  Mapping
this through `isBoundaryNode[-1]` would result in an out-of-bounds
memory access and invalid values in the `vertices_c_style` array.

Closes: #55

Based on the test case provided by Lasse Hinrichsen.

Prepending them to the beginning of the list would mean they are never
visited as the iterator only moves forward.  This required switching to
a `std::list` as the `std::forward_list` does not provide methods to add
items at the end.

This regression was introduced in 20b821be
which replaced `Dune::SLList` with `std::forward_list`, but changed
`push_back` to `push_front` as well.

Closes: #53

If the code path should never be reached, having an exception thrown
makes it easier to nitce it was reached after all.

Pass `OBJECT` option to `add_dune_mpi_flags`

See merge request !140

Apply vertex reordering to boundary segment vertices

Closes staging/dune-uggrid#18

See merge request !145

Adapt to changes of the UG CreateDomain method

See merge request !146

Said method lost three arguments in

  staging/dune-uggrid!45

This patch contains the corresponding changes in the
UGGrid implementation.

UG wants all boundary vertices to be listed before the other ones.
Therefore, the UGGrid GridFactory reorders the vertices before
they get inserted into the actual UGGrid object.

Unfortunately, vertices of explicitly given boundary segments
used the wrong numbering.  Therefore, constructing grids with
explicitly given boundary segments would fail, unless the
vertices happened to be in the correct order.

This fixes staging/dune-uggrid#18

Add missing renumbering in UGGridEntity specialization

See merge request !136

[utility.parmetisgridpartitioner] fix "temporary cannot bind to non-const ref" error

See merge request !142