Bump to version 8.1.1.

Small release for some simple typos and small patches.

pom.xml

@@ -4,7 +4,7 @@
 
 	<groupId>nl.tudelft.jpacman</groupId>
 	<artifactId>jpacman-framework</artifactId>
-	<version>8.1.0</version>
+	<version>8.1.1</version>
 	<url>https://github.com/serg-delft/jpacman-framework</url>
 	<description>
 		Pacman-inspired game, for teaching testing purposes.