Investigate php currency library ( chose brickmoney)

We have a lot of money handling in our code. Our functions are a bit meh. We still seem to hit issues on money calculations that there are libraries to handle....

There seem to be 2 leading contenders https://github.com/moneyphp/money and https://github.com/brick/money (the latter seems slightly nicer based on the docs)

Both seem to rely on php intl extension for formatting currencies - is that a blocker? or is it common, esp on non US sites.

See #47 for js issue on the same