Adding initial Extension for SimpleITK filter from json

This is a prototype of a Slicer Module which uses the SimpleITK JSON
descriptions of ITK filters in a scripted python module to allow
execution in the slicer environment.
Add UpdateFilterDescriptionFromSimpleITK.sh script
Updating UpdateFilterDescription script to reference sitk-upstream

Also cleaned up some reference to the names of repos
Merge branch 'sitk-upstream' into update-sitk
Setting initial input and output nodes
Adding update of filter parameters from vector GUI
Adding rename to output image.

Set number of digits for Coordinate widget based on real or integer
vector type.
removing debug print statements
adding ranges to spin boxes
refactored creation of widgets into fucntions
Adding KernelImageFilter template for radius and kernel type
white space cleanup
Adding fiducials for seeds in region growing and fast marching
print unknown simpelITK argument to stderr
Add a search box for picking the filters
Switch the filter selector to use the data for the index into the json
filter list.
Handle unexpected annotation nodes by ignoring them
adding missing import of sys
Adding test which goes through all the filters in the GUI
code clean up

removed commented out code, tweak a comment, and a print statement