Request - Add support to multiple Currency on Formatting Numbers in Visualizations

[ViniciusFXavier]

Add support to multiple currency on Formatting Numbers in Visualizations.

Documentation: https://redash.io/help/user-guide/visualizations/formatting-numbers
Today just allow $(Dollar), need add possibility to allow multiple currency signals like R$(Brasil Real), ¥(Yen / Yuan), €(Euro) and others.

[deecay]

Maybe it's worth mentioning in the documentation that {} can be used to escape string.
e.g. {€} 0,0.00