Now the application no longer needs to care about the tile origin, because the CacheWrite control modifies the url if the CORS image loading is disabled and it is from a different origin. This only requires OpenLayers.ProxyHost to be properly configured. Also local storage keys use the original url instead of the proxied url, to make the CacheRead control work without proxy settings.
No deferred exceptions are thrown any more. Instead, OpenLayers.Console is used to show an error message for security exceptions.
We now check for OpenLayers.Tile.Image, because other tile types (e.g. UTFGrid) are not supported (yet).
To make the same origin handling in the CacheWrite control easier, OpenLayers.Request now exposes the same origin logic from request.issue as a separate function, so it can also be used by other components.
layer.maxExtent is always set as soon as the layer is added to a map. Instead, making behavior consistent with tiled layers: don't display outside maxExtent except when displayOutsideMaxExtent is set to true or the layer's extent equals the world bounds for maps with a baseLayer that has wrapDateLine set to true.
The UTFGrid layer's `getTileInfo` method was not correctly handling dateline wrapping (and was a bit more complicated than it needed to be). Since it would be useful to all grid layers to be able to retrieve a tile and pixel offset for any map location, this functionality deserves to be on the Grid layer.
The WMTS layer currently exposes a `getTileInfo` method that is used within the layer and by the WMTSGetFeatureInfo control. This method could be renamed to `getRemoteTileInfo` or something to differentiate it from a method that gets locally cached tile info. Until that change is made, the method on the Grid layer will be called `getGridData`.
For this to be useful (i.e. so listeners can see/modify the tile url), a change in Tile.Image is required so we do not fire the loadstart event before we have the url to load.
The zoom control allows for zoom in/out links that can be styled with CSS.
Note: This change was originally captured in #269. It involves nice additions thanks @ahocevar. The changes were unintentionally merged and then reverted with fb3caf1561, so the history of commits is not immediately apparent (though still likely there somewhere due to the magic of git).
