Fix potential logic flaw in getting default server. Need to look into forced servers issue.

src/main/java/net/md_5/bungee/Configuration.java

@@ -254,7 +254,7 @@ public class Configuration
         }
         if (server == null)
         {
-            server = servers.get(defaultServerName);
+            server = defaultServerName;
         }
         return server;
     }