Create performance benchmarks #243
Description
We should create some performance benchmarks for mapbox-gl-draw that are quantifiable and repeatable.
Ideally, these benchmarks would be runnable in a headless environment using something like http://karma-runner.github.io.
It probably makes sense to work on the upstream mapbox-gl-js performance benchmarks first, and use the lessons and infrastructure from those to build the mapbox-gl-draw benchmarks.