Revise item usage and consumption

[krbz999]

The function Item5e#_getUsageConfig returns an object of what an item is able to do:

• Create a template.
• Consume a spell slot.
• Consume limited uses/recharge.
• Consume a resource.

The function Item5e#_getUsageConfigValues returns an object that depends on _getUsageConfig to determine what an item, by default, will do. This is the object that can be modified directly in Item5e#use. This also includes slotLevel, which is now always a string.

Whether an item then needs configuration is determined by if any of the default values are true (they are by default true if the item is able to fulfill their function).

If none are true, a prompt will not be forced. Any boxes that are possible but overridden to be false by default will still appear in the AbilityUseDialog, but unchecked; if the prompt is skipped (options.configureDialog being false) the initial values are used (possibly partially overridden).

Also added two properties in item.system.uses and item.system.target for #2463 which function with getUsageConfigValues.

[Fyorl]

Good changes here, thank you for taking on this refactor. I think you've managed to streamline the logic and make the pipeline a lot easier to follow (at least for me). I have some suggestions for your consideration that we can discuss.

[Fyorl]

I caught a couple more things on re-review, but otherwise this looks pretty much there. I will try for a faster turn around on any comments/changes here. Apologies for the delay.

[Fyorl]

@krbz999 Any thoughts on this? Do you have a strong objection to it?