TaxID: Expand API to allow retrieving or deleting a single TaxID

[feliixx]

API: Add 'object' to the response on Deletion

The goal is to be closer to Stripe API. Also, create a new DeletedObject class that will be easier to use.

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TaxID: Expand API to allow retrieving or deleting a single TaxID

Creating and listing TaxID have been supported for a long time, but retrieving or deleting a single TaxID wasn't implemented, so let's change that.

Stripe doc:

• https://stripe.com/docs/api/customer_tax_ids/retrieve
• https://stripe.com/docs/api/customer_tax_ids/delete

[feliixx]

Thanks for the reviews!