Vault Upgrade

* Vaults now have a maximum limit of 600 items.

* Vaults no longer have a weight or bulk limit.

* You can always store a single stack of items, so that Conveyance
always works.

This will allow players to store unlimited amounts of reagents, and a
large amount of singular items, without making the vault list too long
and causing crashes.

This is one issue where players have us completely outmatched.
If we do not give them unlimited vault space, then, any time they
run out of space, they will simply create a free mule account to
increase their vault space. We can't stop them, and we can't
limit them.

To do away with the issue entirely, this pull will simply make
vaults effectively limitless (while still avoiding overload crashes).