List policy: Please whitelist linuxchix mail

A quick note for people who are using "you cannot send me mail unless you are whitelisted" spam filters: if you subscribe to the linuxchix lists, you must whitelist the lists yourself. The admins will not reply to any "please jump through these hoops to be whitelisted" mails. Such messages will be treated as bounces, and if we get enough of them, we will unsubscribe you, like any other bouncing address.