This registry is the payment target type registry for payto:// URIs.

payto:// URIs include the necessary information for making wire
payments to a recipient. As there are many banking standards globally
with different address formats (such as UPI in India, ACH in USA, IBAN
in Europe), a payto:// URI begins with a string describing the method
used to identify the recipient.  This registry is used to ensure that
the strings used in payment target types are well-defined and to
ideally allow payto:// implementors to find out details about the
respective payment system.
