Attempting to repair an order object leak.

Now frees manager_order objects in the reaction_list when the plugin is disabled or the world unloaded.  However, there may still be orders leaked elsewhere.
Magic number reduction: Persistent storage

Replaces explicit indices into the ints field of Stockflow persistent storage objects with enumerated values.
Magic number reduction: Job types
Magic number reduction: Clothing flags

Bone and shell are used to construct BARRED and SCALED armor/clothing items, for some reason.
Magic Number Reduction: Display placement constants
Clearing the center column.

The official order selection screen has an extra space to the left of the orders on the right-hand side.