Update Changelog to 1.38.4
Update Changelog to 1.38.4

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