Fix inconsistent use of boldface font in credits
The titles ‘Art & scenario:’ and ‘Correctors’ didn’t use a boldface font, while all the other titles did. For the ‘Software:’ and ‘License:’ text, the entire lines were set in boldface, not just titles. And the URL www.peppercarrot.com wasn’t set in boldface for this episode, but was so in earlier episodes. All this is now fixed.