Stateless GetFeatureInfo for ol.source.TileWMS
Stateless GetFeatureInfo for ol.source.ImageWMS
Enable ProjectionLike on getGetFeatureInfoUrl

This commit follows up on #2348.
Rename getfeatureinfo example to getfeatureinfo-tile
Add a getfeatureinfo-image example
Merge pull request #2582 from elemoine/wmsgfi

Support for "Stateless GetFeatureInfo"