communication.

Both Interface and BufferedCommunicator loose their template
parameter. It was not needed and hindered the new implementation.
Sorry for the inconvenience.

Please change your code:
Interface<IndexSet> -> Interface
BufferedCommunicator<IndexSet> -> BufferedCommunicator

[[Imported from SVN: r1084]]

Please merge to release!

[[Imported from SVN: r1083]]

I hope this is the correct of fixing this. Maybe Markus could take a short look
on this...

[[Imported from SVN: r1082]]

[[Imported from SVN: r1081]]

repartitioning.
Do not skip isolated nodes. (In parallel they might occur on coarser
level due a not ideal data decomposition)

[[Imported from SVN: r1080]]

Made parallel SOR work with amg.

[[Imported from SVN: r1079]]

[[Imported from SVN: r1078]]

Adapt to interface change.

[[Imported from SVN: r1077]]

Parallel AMG works on helics with repartitioning!

matrixredistribute.hh : Ensure that overlap rows have the right entries
matrixutils.hh : Added method to print a distributed sparse matrix
amg.hh: initialize pointer with zero to prevent deallocation of nonallocated storage.
hierarchy.hh: print operator complexity in verbose mode.
transfer.hh: removed wrong assertions (yes, Index sets can have holes!)
repartition.hh: Bugfix: Use the correct MPI datatype to unpack. (Unpacking a std::size_t using MPI_INT on 64 bit is not a good idea!)

[[Imported from SVN: r1076]]

[[Imported from SVN: r1075]]

[[Imported from SVN: r1074]]

[[Imported from SVN: r1073]]

ParMETIS. (The additive version is not yet debugged!!!)
Graph::maxVertex does what it says now
Made index sets accessible in RemoteIndices class.
Fixed some typos.

[[Imported from SVN: r1072]]

[[Imported from SVN: r1071]]

redistribute the matrix according to it.

[[Imported from SVN: r1070]]

[[Imported from SVN: r1069]]

[[Imported from SVN: r1068]]

Both do not do any error checking.
Introduced at method that does the same but checks for errors.

[[Imported from SVN: r1067]]

[[Imported from SVN: r1066]]

[[Imported from SVN: r1065]]

information. This needed whenever one wants to add new indices to
the underlying index sets and does not want to recompute the remote
index information.

[[Imported from SVN: r1064]]

Please merge to release.

[[Imported from SVN: r1063]]

parameter is the global id. Additionally omit the second parameter as
it is not needed.

[[Imported from SVN: r1062]]

[[Imported from SVN: r1061]]

[[Imported from SVN: r1060]]

[[Imported from SVN: r1059]]

[[Imported from SVN: r1058]]

[[Imported from SVN: r1057]]

[[Imported from SVN: r1056]]

calculate max distance correctly. 
neigbours method no visits the neighbour and counts them instead of
just returning (0,0). (Fixes the rounding step for the aggregates.)

[[Imported from SVN: r1055]]

- Compiles with g++-4,4 now. Error was error: declaration of
  ‘Dune::SuperLUMatrix<Dune::BCRSMatrix<Dune::FieldMatrix<K, n, p>,
  TA> >& m’shadows template parm ‘int m’ 
  Fixes flyspray #581

- Removed wrong assertion. One should not check whether the whole
  matrix is copied if one just copies a part of it. (Blame copy & paste)

[[Imported from SVN: r1053]]

[[Imported from SVN: r1052]]

[[Imported from SVN: r1049]]

[[Imported from SVN: r1047]]

[[Imported from SVN: r1046]]

The matrix type is also used for the ILU member variable, which is
initialised with a copy of the matrix and then inclompletely LU
decomposed.  This member variable must not be const.

[[Imported from SVN: r1045]]

When initializing coarse aggregate number for visualization make sure that each number is used only once and number are consecutive from 0 but still randomly distributed.

[[Imported from SVN: r1044]]

Randomize coarsest aggregate numbers to get better contrast between
aggregates.

[[Imported from SVN: r1043]]

[[Imported from SVN: r1042]]

[[Imported from SVN: r1041]]