in particular we removed the variables bottomtmpmem, usefreelistmemory
and freelist_end_mark and cleaned up the code using them.

the virtual heap management was only used for user data.
As dune handles user data differently, we can drop this code.

drop ResetCEstatistics, PrintCEstatistics, DefineMGUDBlock,
     FreeMGUDBlock, and GetMGUDBlockDescriptor

try fixing heap cleanup

fixup bottom/top heap

bugfix

check_of_getcallstack and check_of_putcallstack were used to keep track
of calls to the memory management. As most of it is now defered to the
libc calls, we don't need these variables anymore.

 we removed:
 ... HeapSize HeapUsed HeapFree HeapFreelistUsed HeapTotalFree HeapStat

 - we removed these memebers and updated the management code accordingly
 - most status functions in heaps.cc are now a NOP and should be removed

we have kept a few of them in order to keep track of where we could further
simplify the code and remove old code...

the member was used to keep track of the heap memory, but since we use
the system heap the variable is always 0.

these variables were used to chnage the memory mangement of a particular
UG instance. As these variables were global, this could only work by
coincedence. We moved them to the heap, as this is the memory mangement
unit for the multi grid.

  - we compute some sizes, but the name was misspelled, thus we always used the default

Cleanup

See merge request staging/dune-uggrid!98

The rank will no longer be readily available as a global variable once
a context object for PPIF is used.  Also MPI implementations already
provide a way to tag output with the rank of processes, for example
OpenMPI's `mpirun` has the `--tag-output` and `--output-filename`
options.

replace `ArrayOf` implementation with `std::vector`

Closes #17

See merge request !71

clean up DDD and PPIF a bit

See merge request !95