chore(package): update validator to version 4.2.1
chore(package): update validator to version 4.2.1

http://greenkeeper.io/
watson-developer-cloud/visual-recognition-nodejs,filipmadej/visual-recognition-demo,filipmadej/visual-recognition-demo,v3rt1go/devhacks-vr,watson-developer-cloud/visual-recognition-nodejs,oremari/plantDiseaseSymptoms-vr-demo-1483744992341,v3rt1go/devhacks-vr,oremari/plantDiseaseSymptoms-vr-demo-1483744992341