Item database issues.

[trickyloki3]

These are mostly consistency issues from referencing item id or group that does not exist:

• Item ID 15657 does not exist in item database, but Item ID 12538 uses getitem on 15657.
• Item ID 7804 is commented out in item database, but Item ID 13765 uses getitem on 7804.
• IG_MYSTERIOUS_TRAVEL_SACK4 does not have entries in item_package.txt
• IG_UNLIMITED_BOX10 does not have entries in item_package.txt
• Item ID 28183 does not exist in item database, but Item ID 22813 does a callfunc("F_Rand") with the item 28183 in the list.

Compiler have trouble searching for the following constants:
32 - item group related.
255 - item related, but searches all constants tables and databases.

[warn]: failed to map constant 15657 in item 12538 on flag 255
[warn]: failed to map constant 7804 in item 13765 on flag 255
[warn]: failed to map constant 182 in item 13848 on flag 32
[warn]: failed to map constant 405 in item 17278 on flag 32
[warn]: failed to map constant 28183 in item 22813 on flag 255

[nanakiwurtz]

1,2,6 = Done
3. It exists on const.txt: IG_Pet_Egg_Scroll_Box5 = 99
4. Mysterious_Travel_Sack4 (#13848) = No information yet
5. Unlimited_Box(10) (#17278) = No information yet

[trickyloki3]

I made a mistake with IG_Pet_Egg_Scroll_Box5, it has zero entries in item_package.txt just like 4 and 5, which I assume no information is available yet.