BUG: fix shallow copy of old index in iterator method
BUG: fix shallow copy of old index in iterator method

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