MaNGOS merge: Mail System.

* Store loot in mail_loot_template indexed by mail template ids.
* Implement proper creating mail text copy item from mail template based mail.
* Move send functions to new MailDraft class from WorldSession.
* Implement mails sending at player levelup.
* Autor VladimirMangos, converted by me.

--HG--
branch : trunk

src/game/DBCStructure.h

@@ -1104,7 +1104,7 @@ struct MailTemplateEntry
     uint32      ID;                                         // 0
     //char*       subject[16];                              // 1-16
                                                             // 17 name flags, unused
-    //char*       content[16];                              // 18-33
+    char*       content[16];                                // 18-33
 };
 
 struct MapEntry