Fix JS locale data for release of Money 6.19

The money gem in its latest iteration added a space between value and
unit of the Swiss Franc. Our heuristic in `_js_locale_data.html.erb`
can't deal with that, so we add a third branch to it: If the money gem
has a format wish, we'll respect it, but replace its abbreviations with
the one the `accounting.js` library prefers.

(cherry picked from commit f19e6fc)

backend/app/assets/javascripts/spree/backend/format_money.js

@@ -7,5 +7,5 @@ Spree.formatMoney = function(amount, currency) {
   var thousand = Spree.t('currency_delimiter');
   var decimal = Spree.t('currency_separator');
 
-  return accounting.formatMoney(amount, currencyInfo[0], currencyInfo[1], thousand, decimal, currencyInfo[2]);
+  return accounting.formatMoney(amount, currencyInfo[0], currencyInfo[1], thousand, decimal, currencyInfo[2]).trim();
 }

backend/app/views/spree/admin/shared/_js_locale_data.html.erb

@@ -17,11 +17,14 @@
     JSON.dump(
       Spree::Config.available_currencies.map { |c|
         format =
-          if c.symbol == "" || c.symbol_first
+          if c.format.present?
+            c.format.gsub("%u", "%s").gsub("%n", "%v")
+          elsif c.symbol == "" || c.symbol_first
             "%s%v"
           else
             "%v %s"
           end
+
         [c.id.to_s.upcase, [
           c.symbol || "¤",
           c.exponent,