Revert "Don't use :active pseudo-class"

Now seeing this cause poor pan performance.

This reverts commit 9fafd6b56aefa213b0f59de1acae58d5438b608e.
Optimize area rendering

Use iD.svg.Path for caching, and teach iD.svg.Path to
round coordinates.
Eliminate context dependency
Preset#matchTags -> Preset#matchScore