VTK Developers authored Apr 09, 2012 and Brad King committed Apr 09, 2012

Move source files from their former monolithic VTK location to their new
location in modular VTK without modification.  This preserves enough
information for "git blame -M" and "git log --follow" to connect
modularized VTK files to their original location and history.

Co-Author: Marcus D. Hanwell <marcus.hanwell@kitware.com>
Co-Author: Chris Harris <chris.harris@kitware.com>
Co-Author: Brad King <brad.king@kitware.com>
Co-Author: Nikhil Shetty <nikhil.shetty@kitware.com>

This patch introduces 3 new classes:

- vtkPeriodicTable: Convert between atomic number and symbol/name,
  lookup rgb values, lookup atomic radii, etc.
- vtkBODR: Container for arrays parsed from the Blue Obelisk Data
  Repository
- vtkBODRParser: Parser to read the XML files from the bodr.

It also contains bodr's elements.xml file and COPYING notice (MIT
license). These are installed to share/.

Change-Id: Ia7c928250e788695ad22a007dfdc9de4363c0474