Three more late-breaking improvements to the comics aggregator

I’ve squeezed in another few improvements to the comics aggregator today:

1. When the aggregator knows what the “source” page is for a comic image, i.e., the official web page where that image can be found, it will link the image in the aggregator to it so if you click on the image you’ll be taken to its source page.
2. When the aggregator is able to determine the “title” for a comic image, i.e., the text that the browser shows you when you hover your mouse over the image, it will display that title itself just as it is displayed on the image’s official web page. This means you can now get both levels of the joke for xkcd.com directly in the aggregator!
3. The API know supports a json=1 query parameter to request a response in JSON format, which now includes the source and title information. See the user guide for details about the format.