src/listenToMany.js
function() {
            for(var m in ListenerMethods){
                if (this[m] !== ListenerMethods[m]){
                    if (this[m]){
                        throw "Can't have other property '"+m+"' when using Reflux.listenToMany!";
                    }
                    this[m] = ListenerMethods[m];
                }
            }
            this.listenToMany(listenables);
        }
function() {
            for(var m in ListenerMethods){
                if (this[m] !== ListenerMethods[m]){
                    if (this[m]){
                        throw "Can't have other property '"+m+"' when using Reflux.listenToMany!";
                    }
                    this[m] = ListenerMethods[m];
                }
            }
            this.listenToMany(listenables);
        }
Set up the mixin before the initial rendering occurs. Import methods from `ListenerMethods`
and then make the call to `listenTo` with the arguments provided to the factory function