o Added a note about the Terms of Use to the MapQuest OSM tile source

@@ -25,6 +25,11 @@
 // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 // POSSIBILITY OF SUCH DAMAGE.
 
+//
+// Please note the MapQuest Terms of Use for attribution and limitations before using this tile source:
+// http://developer.mapquest.com/web/products/open/map#terms
+//
+
 #import "RMAbstractWebMapSource.h"
 
 @interface RMMapQuestOSMSource : RMAbstractWebMapSource