BUG: UseHistograms was not getting set on ITK filter

Adding test to verify that the median is not updated.

Change-Id: I8f2999c3bf7c1f5c5417d75fccff65bf52dca9f2
Merge branch 'SIMPLEITK-510_AddUseHistogramsOptionToLabelStatistics' into release

* SIMPLEITK-510_AddUseHistogramsOptionToLabelStatistics:
  BUG: UseHistograms was not getting set on ITK filter

Change-Id: Ifa5a140e1438629b30708a57394eaff2a254b541
Merge branch 'release'

Change-Id: I36a387c8a9e497838c66deea0051d372604fa3d2
Merge branch 'master' into next

Change-Id: I2eccf8a23aa264ddb3d8d62974bb756c319eaee4
Updating ITK tag along 4.6.0 release

Change-Id: I9a8591db4e61a79246be742704344736c97c63ce
Merge topic 'SIMPLEITK-543_UpgradeITKTowards4.6' into next

704c92c3 Updating ITK tag along 4.6.0 release