Added instructions to messages.yml.

src/me/ryanhamshire/GriefPrevention/DataStore.java

@@ -1422,6 +1422,7 @@ public abstract class DataStore
 		//save any changes
 		try
 		{
+			config.options().header("Use a YAML editor like NotepadPlusPlus to edit this file.  \nAfter editing, back up your changes before reloading the server in case you made a syntax error.  \nUse dollar signs ($) for formatting codes, which are documented here: http://minecraft.gamepedia.com/Formatting_codes");
 		    config.save(DataStore.messagesFilePath);
 		}
 		catch(IOException exception)