Reworked explanation.
- Hacked up exhibitController to set up two trees displaying the same quadtree.
- More copy edits.
Updated quadtreetree. Setting quadtreetree prefix opt so that the one-at selectors for each tree now work.
- Updated quadtreemap.
- Set up and rendered second quad map.
- Got rid of separate point renderer. Quadmaps handle rendering their own points now.
- Updated exhibitController syncMapToTreeSelection and syncTreeToMapSelection to sync to both maps and both trees, respectively.
- Updated svgcamera, quadtreetree, and quadtreemap.
- Updated exhibitController to instantiate quadtreetrees, quadtreemaps, and cameras in groups and to operate by iterating over those groups.
- Updated quadtreemap and quadtreetree.
- Broke captureElDimensions up into elWidth and elHeight.
- Updated sidebyside quadtree map creation to specify the correct width so that the map rects get are sized proportionally such that they fit the <svg>.