Trigger event when Clusterer redraw method called

[dattarzadeh]

Having an event trigger here will allow the developer to know when the MarkerClusterer is finishing redrawing, and perform additional operations (e.g. manually updating the cluster icons). The paradigm of different clustering icons for 'larger' clusters isn't what we were looking for. The developer can now:

google.maps.event.addListener(myMap, 'clusters_redrawn', function () { // Work... });

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[Remo]

@dattarzadeh this repo isn't maintained anymore, but I'd be happy to review your pull request in our fork: https://github.com/gmaps-marker-clusterer/gmaps-marker-clusterer