Handle event markers with duplicate locations

[iandunn]

When there are several upcoming events in the same location (like a recurring meetup), the Google Map block will show a cluster icon with the number of events. If you click on it to zoom in, though, you'll only see one marker.

One potential solution would be to loop through the markers and spread them apart slightly, so that each has a different set of coordinates, but are still close enough to identify the venue.

Another option would be to remove the later events, and only show the next upcoming event. That may be more desirable in some situations, but wouldn't work in all.

IMO it's probably better for the block to do the first option, and then the caller can do the 2nd if they want.

[iandunn]

Actually, rather than spreading the markers apart, I think it'd be better to condense them into a single marker. The info window could show the details for all of the events, in chronological order.