Update docs for createUser function
Update docs for createUser function

FirebaseExtended/angularfire,douglascorrea/angularfire,fbentz/angularfire,itxd/angularfire,douglascorrea/angularfire,cesarmarinhorj/angularfire,bpietravalle/angularfire,jamestalmage/angularfire,nbr1ninrsan2/angularfire,fbentz/angularfire,nbr1ninrsan2/angularfire,yoda-yoda/angularfire,bpietravalle/angularfire,cesarmarinhorj/angularfire,FirebaseExtended/angularfire,itxd/angularfire,denisKaranja/angularfire,fbentz/angularfire,douglascorrea/angularfire,bpietravalle/angularfire,denisKaranja/angularfire,nbr1ninrsan2/angularfire,jamestalmage/angularfire,denisKaranja/angularfire,FirebaseExtended/angularfire,jamestalmage/angularfire,yoda-yoda/angularfire,itxd/angularfire,cesarmarinhorj/angularfire,yoda-yoda/angularfire