Add ol.Map.getRenderer function
Add ol.renderer.Map.getCanvas function. Only valid with the canvas and webgl renderers
Remove stale dependencies
Export canvas map as jpeg image
Merge pull request #143 from fredj/get-renderer-canvas

Get renderer canvas
Export map as jpeg instead of png
Update readme.md
Merge pull request #145 from elemoine/readme

Update readme.md
Use goog.now() instead of Date.now().

Date.now() is not supported in Internet Explorer up to IE 9. The goog.now()
method can be used as a replacement.
Merge pull request #147 from marcjansen/goog.now

Use goog.now() instead of Date.now().
Export map.getLayers