Add Events object as a helper for installing and removing events.

src/paper.js

@@ -48,6 +48,7 @@ this.install = function(scope) {
 
 //#include "util/CanvasProvider.js"
 //#include "util/MathUtils.js"
+//#include "util/Events.js"
 //#include "util/PaperScript.js"
 
 };

src/util/Events.js

@@ -0,0 +1,28 @@
+var Events = {
+	add: function(obj, events) {
+		for (var type in events) {
+			var func = events[type];
+			if (obj.addEventListener) {
+				obj.addEventListener(type, func, false);
+			} else if (obj.attachEvent) {
+				// Make a bound closure that calls on the write object and
+				// passes the event object.
+				obj.attachEvent('on' + type, func.bound = function() {
+					func.call(obj, window.event);
+				});
+			}
+		}
+	},
+
+	remove: function(obj, events) {
+		for (var type in events) {
+			var func = events[type];
+			if (obj.removeEventListener) {
+				obj.removeEventListener(type, func, false);
+			} else if (obj.detachEvent) {
+				// Remove the bound function instead of func itself
+				obj.detachEvent('on' + type, func.bound);
+			}
+		}
+	}
+};