BUG: set the statistics member variables
BUG: set the statistics member variables

This filter was designed to run and set the simpleITK member variable
from ITK. These were not set and the filter didn't do anything before.

SIMPLEITK-53

SimpleITK/SimpleITK,hendradarwin/SimpleITK,SimpleITK/SimpleITK,richardbeare/SimpleITK,InsightSoftwareConsortium/SimpleITK,InsightSoftwareConsortium/SimpleITK,InsightSoftwareConsortium/SimpleITK,richardbeare/SimpleITK,richardbeare/SimpleITK,InsightSoftwareConsortium/SimpleITK,kaspermarstal/SimpleElastix,hendradarwin/SimpleITK,hendradarwin/SimpleITK,kaspermarstal/SimpleElastix,InsightSoftwareConsortium/SimpleITK,richardbeare/SimpleITK,richardbeare/SimpleITK,SimpleITK/SimpleITK,richardbeare/SimpleITK,blowekamp/SimpleITK,blowekamp/SimpleITK,kaspermarstal/SimpleElastix,SimpleITK/SimpleITK,blowekamp/SimpleITK,hendradarwin/SimpleITK,blowekamp/SimpleITK,blowekamp/SimpleITK,hendradarwin/SimpleITK,blowekamp/SimpleITK,kaspermarstal/SimpleElastix,InsightSoftwareConsortium/SimpleITK,SimpleITK/SimpleITK,SimpleITK/SimpleITK,kaspermarstal/SimpleElastix,blowekamp/SimpleITK,hendradarwin/SimpleITK,InsightSoftwareConsortium/SimpleITK,hendradarwin/SimpleITK,SimpleITK/SimpleITK,richardbeare/SimpleITK,kaspermarstal/SimpleElastix,blowekamp/SimpleITK,hendradarwin/SimpleITK,InsightSoftwareConsortium/SimpleITK,SimpleITK/SimpleITK,kaspermarstal/SimpleElastix,richardbeare/SimpleITK