CRUD operations for SecurionPay customers.

Customers allows to store cards for later use and to perform automatically recurring charges. Customers are also useful for tracking charges that are associated with the same entity.

Corresponding docs for the original REST APIs.

Prelude to the examples

iex> customer_id = Securion.Customer.create("foo@example.com")

iex> token_id = Securion.Token.create()