remove 'comparison between signed and unsigned integer expressions' warning.
avoid some signed/unsigned warnings
[CMake] add -DENABLE_ALUGRID to ALL_PKG_FLAGS if ALUGrid is found
remove warning: comparison between signed and unsigned integer expressions
Deprecated ALUGrid. Use DUNE-ALUGrid instead.
remove warning.
[dgf] remove unused include

Historically, the dgf entity key depended on ALUGrid's element
numbering. Since the introduction of the grid factory, this is no longer
the case. However, there was a left-over include to ALUGrid's topology
mapping, which causes trouble in combination with dune-alugrid. This
patch removes this unused include.
[REWRITE] Yasp has all entities and communication.

This is a major rewrite of Dune::YaspGrid. It now
- has full entities of all codimensions
- communicates on all these codimensions
- works for arbitrary dimension (again)

Of course, these new features come at a price.
The performance implications in comparison to the old
code have been measured. Iterating over the grid and
computing indices and subindices got a bit slower
(to a maximum of 20%). However, these operations are
still really (!) fast.

Here are some implications for the implementation
(not of interest for users):
- The former YGrid is now called YGridComponent. All entities
  that belong to one such component share the same "shift"
  (the set of spanning unity vectors). For codim 0 and dim,
  there was only one component describing a codimension, in
  general this is dim choose codim.
- A YGrid is a collection of YGridComponent. A YGrid
  describes the parts of a grid given by partition type
  and a codimension. It offers iterators to iterate over
  the multiple components. YGridList does the same thing
  for send and receive lists.
- Yasp handles codimensions generically now. The former
  data structures {cell,vertex}_{...} are replaced by
  arrays of size dim + 1 of {...}.
- The entity implementation provides a generic implementation
  of the index methods according to the new generic reference
  elements.
- A namespace Yasp is introduced and used to hide away some
  free functions from the user.
- YaspGeometry now handles the bitsets required by
  AxisAlignedCubeGeometry directly.

The incode and doxygen documentation of the rewritten code
was improved whenever it seemed necessary.
count --> subEntities.
commented unused variable out.
remove unused typedefs.
[docufix] intersectionSelfLocal --> geometryInInside.
[bugfix] intersectionGlobal --> geometry.
added some docu on method geometry for intersections.
[cleanup] Remove obsolete comments
[cleanup] spelling
Simplify the implementation of YLoadBalancePowerD

And make the error message more helpful.
remove warning.
[vtkwriter] fix parallel vtk sequence writer

the pvd file didn't point to the parallel pvtu files, but to the sequential rank-0 file. We now
use the correct method to retrieve the fullname from vtkwriter & co.
[release,bugfix] Use the same ALBERTA${N}D_LIBS for installed and local dune-grid.

Previously we modified ALBERTA_LIBS in configure.ac as some of the variables
used there are only set in downstream modules. In addition there was a check
whether dune-grid is installed during setting the alberta libraries in
m4/alberta.m4. Unfortunately this never worked as the variables were not
yet set at this point.

Now we simply set DUNE_GRID_LIBDIR in configure.ac and use the same stanza for
setting the alberta libs
ALBERTA${N}D_LIBS="'-L\$(DUNE_GRID_LIBDIR) -ldunealbertagrid_${N}d -ldunegrid \$(ALBERTA_LIBPATHFLAGS) -lalberta_${N}d \$(ALBERTA_BASE_LIBS)'")
no matter whether dune-grid is installed or not and rely on libtool to do
the magic.

Fixes flyspray 1414 https://dune-project.org/flyspray/index.php?do=details&task_id=1414
as confirmed by Ansgar. Kudos to him for testing.