Cleaned up item flags: separated item proto flags and item field flags

Implemented use of:
ITEM_PROTO_FLAG_PROSPECTABLE and ITEM_PROTO_FLAG_MILLABLE now checked instead of bag family mask
ITEM_PROTO_FLAG_SMART_LOOT for profession recipes, player has to have skillline and not know the recipe
ITEM_PROTO_FLAG_OPENABLE item has to have it set to use item_loot_template
ITEM_PROTO_FLAG_NOT_USEABLE_IN_ARENA if this is set item can never be used in arena
ITEM_FLAG_UNLOCKED marks unlocked items

Simplified BoA check for mail sending
Stackable items are no longer refundable
Removed useless code that always set ITEM_FIELD_FLAGS equal to proto flags
Unlocking items (lockpicking) is now blizzlike

--HG--
branch : trunk

sql/updates/9160_characters_item_instance.sql

@@ -0,0 +1,3 @@
+SET @allowedFlags := 0x00000001 | 0x00000008 | 0x00000200 | 0x00001000 | 0x00008000 | 0x00010000;
+
+UPDATE `item_instance` SET `flags` = (`flags` & @allowedFlags);