Merge branch 'master' of https://github.com/danvk/dygraphs

Conflicts:
	dygraph.js

diff --cc dygraph.js
index f5e19ab,657a405..bd582cb
--- 1/dygraph.js
--- 2/dygraph.js
+++ b/dygraph.js
@@@ -1470,7 -1402,7 +1476,7 @@@ Dygraph.prototype.mouseMove_ = function
    var points = this.layout_.points;
  
    // This prevents JS errors when mousing over the canvas before data loads.
-   if (points === 'undefined') return;
 -  if (typeof(points) == 'undefined') return;
++  if (points === undefined) return;
  
    var lastx = -1;
    var lasty = -1;