Introducting a work in progress version 0.2

- GTK backend works again, but again is a mess
- New document format. Old Refcat (which I don't think there is any) documents for version 0.1 do not work any more. But, the new format is similar (it's packaged up as HTML to allow for easy sharing, just open the .refcat file in a web browser!)
- Web GUI is a WIP right now
Authors are now rendered as they should be Harvard-style

Also you can Ctrl+C to exit ReferenceCat!