Implemented functionality to compute the error in
the data-transfer for the gaussian pulse transfer
example.

Added a gaussian pulse solution over the grids as a
sample solution for the given grid system.

Change-Id: I6b2268e2c8e817e8c5e47a7eed0651214bca86cc

Called Delete() on the vtkMPIController after
Finalize() and inserted other Delete() as approriate
so that there are no memory leaks.

Fixed construction of sample problem, s.t.,
high resolution cells covers the entire low
resolution cells, i.e., no partial overlap.
Furthermore, vtkXMLHierarchicalBoxWriter is
used to write the data-set.

Removed all the internal I/O to generate legacy
VTK files. vtkImageToStructuredGrid is used instead.

Added some print out statements for debugging

Added calls in the AMRDataTransferPipeline for
inter-block & inter-level data-transfer.

Fixed construction of vtkHierarchicalDataSet and
added vtkAMR library to list of target link libraries.

A simple utility to test and demonstrate the
functionality for AMR inter-block data-transfer.