* Add support in Delegate and Revoke for Authority, Data,
CollectionItem, and ProgrammableConfigItem Metadata
delegates.
* Remove Update Metadata delegate.

* Modify authority check to separate out item and
collection-level delegates.
* Add V2 Update args struct to allow user to specify token
standard.
* Check that new delegates are only changing metadata
for which they are meant to have access.
* Modify Update handler to update metadata fields based
on the delegate type.

* Also add macro to help destructure UpdateArgs fields.

* Update is still changed to Data but order is preserved.
* Also remove unnecessary Option for token_record in Update.
* Add some comments clarifying authority types in Unverify.

* Return the value derived in the delegate method.
* Also add a test for Authority delegate.

* Creation time set when PDA is created.
* Expiration checked during get_authority_type.
* This is a draft idea that passes existing tests,
but expiration functionality has not been thoroughly
tested.