Fixing The Cell Binning

Cells could not belong to multiple bins causing wrong
binning behavior in cases where the cell bounding box
intersects bin boundaries.
By inflating the cell bounding box by a small tolerance value,
the cell will be associated correctly to all bins it intersects.

Adding A Test For StaticCellLocator Edge Cases

Adding a test to cover edge cases of the methods
FineCellsAlongLine and FindClosesPointWithinRadius.

Adding Test Data

Adding the testing data for the new vtkStaticCellLocator test.