The exception is not used anywhere and does not make much sense.
Functions/methods which are not implemented yet can just throw
std::runtime_error wich a more specific message.

Build of tools can be turned-off. Grid traversers for 1D and 2D has been rewritten using subdomain overlaps.

double works, not tested for other types.

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)

Fix DistributedGrid_Base - add missing getEntitiesCount - providing global grid entity count - used in tnl-lbm