Disable PM's from login for non-P2P/Classic

[Crono]

Recently it's been abused by phishers and anti-Graalians as a way to spam every person on every server with PM's linking them to "Graal hacks" and whatnot. I propose disabling PM's from the login server fom un-upgraded accounts to prevent this. If they try to log on playerworlds, we can simply ban them (unlike the login server, where only globals can deal with them).