Dirk draw events that are only partially in timeline

Problem 1
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Events are drawn only when fully within the temporal bounds formed by the timeline (if not animating) / brush (if animating).

Solution 1
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Draw events if they're at least partially contained (a.o.t. completely contained) within those temporal bounds.

Problem 2
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There is inconsistent drawing of the events within the timeline (not within map). Sometimes toggling an event series on / off in the layerGroup menu will not redraw it, sometimes on page load only half of the series get
drawn correctly, etc: 

inconsistent behaviour galore..

Solution 2
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Decomplicate the applicable ENTER / UPDATE / EXIT cycli. This is fixed, but the opacity animation for ENTER phase is a goner.