Adding unit test for lower_keys
Adding unit test for lower_keys

gdestuynder/MozDef,mozilla/MozDef,gdestuynder/MozDef,jeffbryner/MozDef,Phrozyn/MozDef,Phrozyn/MozDef,mozilla/MozDef,jeffbryner/MozDef,Phrozyn/MozDef,jeffbryner/MozDef,mpurzynski/MozDef,gdestuynder/MozDef,mozilla/MozDef,mpurzynski/MozDef,mpurzynski/MozDef,mozilla/MozDef,mpurzynski/MozDef,gdestuynder/MozDef,Phrozyn/MozDef,jeffbryner/MozDef