message: Clean-up Token termin usage in payment design.
diff: -# Tokens Interface
  +# Payment Interface
  This design proposes to make libindy aware about payments and tokens that can be implemented with Indy infrastructure.
  @@ -33,7 +33,7 @@ This design proposes to make libindy aware about payments and tokens that can be
  handlers.
  * Payments interface must be interoperable as possible between different payment methods.
  -![Tokens Interface](./payment-interface.svg)
  +![Payment Interface](./payment-interface.svg)
  ## Payment Method API and Payment Method Handler Interface
  