Upgrade to GitHub Site plugin 0.12

Author: joschi

pom.xml

@@ -153,7 +153,7 @@
             <plugin>
                 <groupId>com.github.github</groupId>
                 <artifactId>site-maven-plugin</artifactId>
-                <version>0.9</version>
+                <version>0.12</version>
                 <configuration>
                     <path>${project.version}</path>
                     <message>Maven site for ${project.name} ${project.version}</message>