Ignore Case when looking up arenas by name.

This makes commands case insensitive, e.g. /ma join. Note that arenas with the same name but different casing are considered the same arena, and one of them will be ignored during config-file parsing.

src/main/java/com/garbagemule/MobArena/ArenaMasterImpl.java

@@ -225,7 +225,7 @@ public class ArenaMasterImpl implements ArenaMaster
 
     public Arena getArenaWithName(Collection<Arena> arenas, String configName) {
         for (Arena arena : arenas)
-            if (arena.configName().equals(configName))
+            if (arena.configName().equalsIgnoreCase(configName))
                 return arena;
         return null;
     }