change the datatype of the variable numberOfNodes aka numberOfLBnodes (fka size_Mat) to unsigned long long ... with respect to large grids (>100e^6 Nodes per Level) ... in this regard the 27 directions are changed to size_t and some control variables are also changed to size_t

rename blade*DOld to blade*DPreviousTimestep

This reverts commit cc7bb07a.

The refactored version using std::find instead of std::unique does not work for vectors containing a zero as a receiving index.  For example this is the case in the app BoundaryLayer --> revert to the old version.