disallow/undo rotation at low zooms and near world edge

src/map/map.cpp

@@ -312,6 +312,14 @@ void Map::stopScaling() {
     update();
 }
 
+double Map::getMinZoom() {
+    return transform.getMinZoom();
+}
+
+double Map::getMaxZoom() {
+    return transform.getMaxZoom();
+}
+
 
 #pragma mark - Rotation
 
@@ -356,6 +364,10 @@ void Map::stopRotating() {
     update();
 }
 
+bool Map::canRotate() {
+    return transform.canRotate();
+}
+
 
 #pragma mark - Toggles