feat(leap bind)

Enables easy binding of frame data to a scope.

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<div leap-bind="{hands: 'hands'}" style="position:absolute;left:{{hands[0].palmPosition[0]}}px">{{hands[0].palmPosition[0]}}</div>

<div leap-bind="{hands: 'hands'}"
       leap-bind-update-rate="1000"
       style="position:absolute;left:{{hands[0].palmPosition[0]}}px">{{hands[0].palmPosition[0]}}</div>
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@PascalPrecht have you time to review?