Return rather than fail if resolution is not defined
Enable ProjectionLike on getGetFeatureInfoUrl
Merge pull request #2348 from probins/getget

Enable ProjectionLike on getGetFeatureInfoUrl
Merge pull request #2527 from pagameba/cluster-fix

Return rather than fail if resolution is not defined
Add ol.geom.Polygon#getExteriorRing function
Add ol.geom.Polygon#getInteriorRingCount function
Add ol.geom.Polygon#getInteriorRing function