Fixed missing parenthesis in toString

Author: GabrielePrestifilippo

src/geom/Position.js

@@ -196,8 +196,8 @@ define([
          */
         Position.prototype.toString = function () {
             return "(" + this.latitude.toString() + "\u00b0, " + this.longitude.toString() + "\u00b0, "
-                + this.altitude.toString();
+                + this.altitude.toString() + ")";
         };
 
         return Position;
-    });
+    });