- There is an RAII wrapper called ScopedInitializer to handle
  finalization due to C++ exceptions and to avoid calls to Finalize in
  all exit branches.
- Fixed signature of MpiCommunicator::Init to match that of MPI_Init.

Fixed definition of static members in communicators when the header files are used in multiple translation units

Add StaticVectorFor - for cycle doing all combinations of directions

Heavy Refactorization of DistributedGrids:
	-> Reordered Directions
	-> Add some useless Direction helper functions
	-> Set Up DistributedGrid_Base - shared base with dim template parameter
	-> Add support for communicationGroup created for DistributedGrid (MPI communicator support)

Preapare Distributed Grids for Communication groups (aka MPI Communicator)

Code refactoring.

Added parallel reduction to communicators.

Added command line arguments for a grid domain decomposition setup.

Added MPI info logs.

Only MPICommunicator and DistributedGrid is implemented.