Handle plugin prefixes using Log4J configuration

Display logger name in the console for all loggers except the
root logger, Bukkit's logger ("Minecraft") and Minecraft loggers.
Since plugins now use the plugin name as logger name this will
restore the plugin prefixes without having to prepend them manually
to the log messages.

Logger prefixes are shown by default for all loggers except for
the root logger, the Minecraft/Mojang loggers and the Bukkit loggers.
This may cause additional prefixes to be disabled for plugins bypassing
the plugin logger.

paper-server/src/main/java/org/spigotmc/SpigotConfig.java

@@ -284,7 +284,7 @@ public class SpigotConfig
     private static void playerSample()
     {
         SpigotConfig.playerSample = SpigotConfig.getInt( "settings.sample-count", 12 );
-        System.out.println( "Server Ping Player Sample Count: " + SpigotConfig.playerSample );
+        Bukkit.getLogger().log( Level.INFO, "Server Ping Player Sample Count: {0}", playerSample ); // Paper - Use logger
     }
 
     public static int playerShuffle;