Async initialization for DateFormat

pkg/intl/data/dates/symbols/zu.json

Index: pkg/intl/data/dates/symbols/zu.json
===================================================================
--- pkg/intl/data/dates/symbols/zu.json	(revision 0)
+++ pkg/intl/data/dates/symbols/zu.json	(revision 0)
@@ -0,0 +1 @@
+{"DATEFORMATS":["EEEE dd MMMM y","d MMMM y","d MMM y","yyyy-MM-dd"],"NARROWWEEKDAYS":["S","M","B","T","S","H","M"],"STANDALONESHORTMONTHS":["Jan","Feb","Mas","Apr","Mey","Jun","Jul","Aga","Sep","Okt","Nov","Dis"],"ERANAMES":["BC","AD"],"FIRSTWEEKCUTOFFDAY":5,"NARROWMONTHS":["J","F","M","A","M","J","J","A","S","O","N","D"],"STANDALONESHORTWEEKDAYS":["Son","Mso","Bil","Tha","Sin","Hla","Mgq"],"FIRSTDAYOFWEEK":6,"STANDALONEWEEKDAYS":["Sonto","Msombuluko","Lwesibili","Lwesithathu","uLwesine","Lwesihlanu","Mgqibelo"],"WEEKDAYS":["Sonto","Msombuluko","Lwesibili","Lwesithathu","uLwesine","Lwesihlanu","Mgqibelo"],"QUARTERS":["ikota yoku-1","ikota yesi-2","ikota yesi-3","ikota yesi-4"],"ERAS":["BC","AD"],"MONTHS":["Januwari","Februwari","Mashi","Apreli","Meyi","Juni","Julayi","Agasti","Septhemba","Okthoba","Novemba","Disemba"],"TIMEFORMATS":["h:mm:ss a zzzz","h:mm:ss a z","h:mm:ss a","h:mm a"],"SHORTWEEKDAYS":["Son","Mso","Bil","Tha","Sin","Hla","Mgq"],"SHORTQUARTERS":["Q1","Q2","Q3","Q4"],"WEEKENDRANGE":[5,6],"STANDALONENARROWWEEKDAYS":["S","M","B","T","S","H","M"],"AVAILABLEFORMATS":null,"NAME":"zu","AMPMS":["AM","PM"],"STANDALONEMONTHS":["uJanuwari","uFebruwari","uMashi","u-Apreli","uMeyi","uJuni","uJulayi","uAgasti","uSepthemba","u-Okthoba","uNovemba","uDisemba"],"SHORTMONTHS":["Jan","Feb","Mas","Apr","Mey","Jun","Jul","Aga","Sep","Okt","Nov","Dis"],"STANDALONENARROWMONTHS":["J","F","M","A","M","J","J","A","S","O","N","D"]}