Move top-level typedefs to typedefs.js

With one exception, those directly in the `ol` namespace can be moved without problem.
Some left-over goog.requires are also removed.

src/ol/control/mousepositioncontrol.js

@@ -5,7 +5,6 @@ goog.provide('ol.control.MousePosition');
 goog.require('ol.events');
 goog.require('ol.events.EventType');
 goog.require('ol.Object');
-goog.require('ol.TransformFunction');
 goog.require('ol.control.Control');
 goog.require('ol.proj');
 goog.require('ol.proj.Projection');