fix: name default exports

Author: tsvetomir

src/cldr/date-field-name.js

@@ -1,6 +1,6 @@
 import { localeInfo } from './info';
 
-export default function(options, locale = "en") {
+export default function dateFieldName(options, locale = "en") {
     const info = localeInfo(locale);
     const dateFields = info.calendar.dateFields || {};
     const fieldNameInfo = dateFields[options.type] || {};