ENH: Adding method to set global physical space tolerance

Adding global variables and accessors to the ImageToImageFilter to
allow setting the initial value for tolerances used to verify that the
physical location of image corresponds.

Change-Id: I69e8af8cfe1fb43e5e2807bc34451907bc9fe3f7
Merge topic 'AddGlobalDefaultTolerance'

9087aa4c ENH: Adding method to set global physical space tolerance