I modified the reading of pvti, pvtr and pvts files to handle the case 
where the piece extent was a subset of the whole extent. The vtk readers
allocate an array the size of whole extent and only set the portion
corresponding to the piece extent. This left portions of the array 
uninitialized and caused problems. The reader now copies the array into 
a smaller array the size of the piece extent.



git-svn-id: http://visit.ilight.com/svn/visit/trunk/src@21333 18c085ea-50e0-402c-830e-de6fd14e8384