Add spaceSeparatedCurrency config option

[anna-sunberg]

Add spaceSeparatedCurrency so that it would be possible to have space separated abbreviation but no space after prefixed currency e.g. $10 k

Fixes #423

[BenjaminVanRyseghem]

Thanks for the PR.

Could you change your code so that spaceSeparatedCurrency defaults to spaceSeparated when not specified, so that we can ensure backward compatibility

Something like

spaceSeparatedCurrency = spaceSeparatedCurrency !== void 0 ? spaceSeparatedCurrency : spaceSeparated;

Note: void 0 is the most correct way to refer to undefined as undefined could be locally shadowed

Could you also add a set of tests specific to this feature (I haven't seen them at least 😄)?

Finally, could you add yourself to then AUTHORS file as well as a line in the CHANGELOG?

Thanks again!

[anna-sunberg]

Added the fallback logic and a couple of tests.

Can't add language tests because there's no way to pass that configuration to the old format (although it works in numeral so it shouldn't be impossible to achieve).

[BenjaminVanRyseghem]

Hi :)

despite what GitHub is saying (I quite fucked up while rebasing 😄) your PR has been merged 😄

Thanks again