Added the Lat49.AdHelper.cycleAdsForScreen() method for automatically cycling ads over the tiles visible on the screen (as described in Section 4.2). This method is useful for applications that do not provide events pointing to map locations.
Also added support for choosing Mercator or "unprojected" projections when getting ads based on pixel location (also described in Section 4.2). Previous versions of the API always (erroneously) assumed "unprojected" maps.