Add new illustrations, update licenses

sticker-bay/promo-1/README.md

@@ -31,11 +31,23 @@
 ##### *Fedi-YaY* image
 * LICENSE: Use this image, crediting the author; if you modify it, release it under the same license - CC-BY-SA.
 
+##### *PeerTube Hygiene* image
+* LICENSE: Use this image, crediting the author - CC-BY.
+
+##### *Common Mission* image
+* LICENSE: Use this image, crediting the author - CC-BY.
+
+##### *Purple party 13/2021* image
+* LICENSE: Use this image, crediting the author - CC-BY.
+
+##### *Mascots 13/2021* image
+* LICENSE: Use this image, crediting the author - CC-BY
+
 ##### Credits
 * Mastodon elephants from the official [press kit](https://joinmastodon.org/press-kit.zip) and from *joinmastodon.org* website, by its respective author
 * Levitating GNU by [Nevrax Design Team](https://www.gnu.org/graphics/meditate.html)
-* PeerTube octopus based on [David Revoy](https://www.davidrevoy.com)'s artwork.
-* Head of Misskey Indigo tyan mascot - author and license unknown
+* PeerTube octopus and Mobilizon fennec based on [David Revoy](https://www.davidrevoy.com)'s artwork.
+* Misskey Ai mascot - author and license unknown
 
 #### Note on license
 Some images contain graphics with unknown license. Most likely you'll have no problems using this work or any work based on it in your promotional materials and blog posts.