Clone of markerclustererplus, but works with npm out of the box.
Just like the base module https://github.com/googlemaps/v3-utility-library/tree/master/markerclustererplus this version is also under the Apache 2.0 license.
Markerclusterer Plus : Copyright 2014 Google Inc. All rights reserved.
NPM package © Mike Saidani hello@mikesaidani.com