UMIP 159 - Add NZDUSD price identifier on Polygon

Currently UMA supports many Forex price indexes both on Ethereum and Polygon. We in Jarvis are looking to introduce a new synthetic stablecoin on Polygon - New Zealand Dollar. For that we need the NZDUSD price identifier to be registered in the IdentifierWhitelist contract on Polygon.

Community Review Call outcome - 11th April

GO with conditions

  • remove reference to polygon so that identifier can be used on all supported chains
  • Address github comments.