Update MaxVersion check to be inclusive

src/de/steamwar/linkage/LinkageProcessor.java

@@ -308,7 +308,7 @@ public class LinkageProcessor extends AbstractProcessor {
             }
             if (maxVersion != null) {
                 buildPlan.addImport("de.steamwar.core.Core");
-                checks.add("Core.getVersion() < " + maxVersion.value());
+                checks.add("Core.getVersion() <= " + maxVersion.value());
             }
             if (pluginChecks.length != 0) {
                 buildPlan.addImport("org.bukkit.Bukkit");