Create a Customer

SCAYLE allows you to create a customer.

param name	type	description
`referenceKey`	`String`	External reference set by the client to integrate a third party system
`firstName`	`String`	First name of the customer
`lastName`	`String`	Last name of the customer
`gender`	`String`	Gender of the customer mentioned as per defined ENUM as "`m`", "`f`", "`d`"
`birthDate`	`String`	Date of birth of the customer in YYYY-MM-DD format
`email`	`String`	Email address of the customer
`phone`	`String`	Phone number of the customer
`publicKey`	`String`	Public reference set by the client to display to customers in account areas and transactional emails
`title`	`String`	User-defined title. It can be set to NULL otherwise
`identities`	`Array<CustomerIdentityProvider>`	An array of identity providers used by the customer

param name	type	description
`identityProviderCode`	`String`	The code of an Identity Provider
`externalUserId`	`String\|null`	The user ID provided by the Identity Provider