Update filter to get input map-projection string from the pipeline

Works with VTK commit 8242cdc, which is not been merged as of 22-Dec-2014
Update vtkRasterFeature to use vtkRasterReprojectionFilter

So application code no longer has to deal with map projections (yay)
Input projection is taken from field data, but can still be overridden
Also fixed bug in vtkGDALRasterConverter