Auction house changes:

- Stop storing guid for auctioneer.
 - Store instead house ID
 - No separate ID for various houses. Only Horde, Alliance and Neutral.
 - Removed non-needed faction checks.
 - Use enum for auction house IDs

NOTE: This will expire all current auctions and return item to player (or
award to high bidder) in order to prepare database for the changes.

sql/updates/characters/2015_09_28_00_characters_335.sql

@@ -0,0 +1,5 @@
+UPDATE `auctionhouse`
+SET `time` = 0, `auctioneerguid` = 7;
+
+ALTER TABLE `auctionhouse`
+  CHANGE COLUMN `auctioneerguid`    `houseid`   TINYINT(3)  UNSIGNED NOT NULL DEFAULT '7' AFTER `id`;