fix(dataloader): fix bug where the watch handler fires off even though the ajax requests hasnt returned

we need to wait for the requests to return before trying to parse the selectors and we also don't try and do any work in the controllers that work on the data when the loading flag is still `true`

this error was replicated locally and on http://mrmrs.github.io/rprtr (it was consistent whenever i tried to load the new york times)

* localhost
    ![screen shot 2013-11-08 at 10 09 47 pm](https://f.cloud.github.com/assets/354746/1506068/2f162e3c-4909-11e3-95a6-de804fad358d.png)

* http://mrmrs.github.io/rprtr
    ![screen shot 2013-11-09 at 12 36 34 am](https://f.cloud.github.com/assets/354746/1506277/1be63f12-491a-11e3-9182-994f3621b15e.png)