[#19,routing][m]: introduce Backbone routing and use it for navigation between grid and graph views.

Some substantial other related changes:

* Switched DataExplorer view to have element it attaches to passed in rather than being created internally (this was important for FlotGraph to set up correctly).
  * Also refactored DataExplorer setup somewhat (e.g. got rid of draw function which wasn't needed -- merging necessary parts with initialize)
* Substantial refactoring of FlotGraph so that we correctly work around flot's delicateness regarding rendering (element must not be hidden etc -- see comments in code)
  * Also generally cleaner code

demo/js/app.js

@@ -4,9 +4,9 @@ $(function() {
   window.$container = $('.data-explorer-here');
   var dataset = demoDataset();
   window.dataExplorer = new recline.View.DataExplorer({
-    model: dataset
+    el: window.$container
+    , model: dataset
   });
-  window.$container.append(window.dataExplorer.el);
   setupLoadFromWebstore(function(dataset) {
     window.dataExplorer.remove();
     window.dataExplorer = null;