refactor redraw into pubsub and autoredraw

- pubsub is a basic pubsub impl
- autoredraw is glue code to register callback to pubsub and onevent

moved e.redraw to autoredraw

api/redraw.js

@@ -1,12 +0,0 @@
-"use strict"
-
-module.exports = function(renderers) {
-    return function() {
-        if (renderers.length === 0) return
-        if (renderers.length === 1) return renderers[0]()
-        
-        for (var i = 0; i < renderers.length; i++) {
-            renderers[i]()
-        }
-    }
-}