Export ol.ObjectEvent#key property
Add getTileUrlFunction in ol.source.TileImage
Add getTileLoadFunction and setTileLoadFunction in ol.source.TileImage
Merge pull request #2133 from fredj/ol.ObjectEvent.key

Export ol.ObjectEvent#key property
Document Map.render() and Map.renderSync()
Add ol.FeatureOverlay tests
Merge pull request #2155 from probins/rendersync

Document Map.render() and Map.renderSync()
Merge pull request #2121 from oterral/utils_func_cache

Add getters and setters for TileUrlFunction and TileLoadFunction properties
Merge pull request #2156 from elemoine/featureoverlaytests

Add ol.FeatureOverlay tests
Make getFeatureById method exportable
Add interface for map events so properties can be disambiguated
Make map property of ol.MapEvent exportable
Make frameState property of ol.MapEvent exportable
Merge pull request #2161 from tschaub/exports

Map event and vector source exports.
Graticule component (WIP)