Some typos fixed and improved PDF export

Just to quickly inform that:

• Some typos were fixed (this is why you hire proofreaders, folks, something I didn't do, heh).
• The PDF export has been improved thanks to the help of the Internet Janitor (Decker's creator). Now, the navigation buttons don't appear anymore (except on the first page), giving a proper zine feel to it when reading in PDF (and ready for printing, if you so wish).

Also, be a little patient in case you click to download the PDF. The zine might freeze for a few seconds because Decker is actually rendering it in real-time.