Async initialization for DateFormat

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

Index: pkg/intl/data/dates/symbols/ar.json
===================================================================
--- pkg/intl/data/dates/symbols/ar.json	(revision 0)
+++ pkg/intl/data/dates/symbols/ar.json	(revision 0)
@@ -0,0 +1 @@
+{"DATEFORMATS":["EEEE، d MMMM، y","d MMMM، y","dd‏/MM‏/yyyy","d‏/M‏/yyyy"],"NARROWWEEKDAYS":["ح","ن","ث","ر","خ","ج","س"],"STANDALONESHORTMONTHS":["يناير","فبراير","مارس","أبريل","مايو","يونيو","يوليو","أغسطس","سبتمبر","أكتوبر","نوفمبر","ديسمبر"],"ERANAMES":["قبل الميلاد","ميلادي"],"FIRSTWEEKCUTOFFDAY":4,"NARROWMONTHS":["ي","ف","م","أ","و","ن","ل","غ","س","ك","ب","د"],"STANDALONESHORTWEEKDAYS":["الأحد","الاثنين","الثلاثاء","الأربعاء","الخميس","الجمعة","السبت"],"FIRSTDAYOFWEEK":5,"STANDALONEWEEKDAYS":["الأحد","الاثنين","الثلاثاء","الأربعاء","الخميس","الجمعة","السبت"],"WEEKDAYS":["الأحد","الاثنين","الثلاثاء","الأربعاء","الخميس","الجمعة","السبت"],"QUARTERS":["الربع الأول","الربع الثاني","الربع الثالث","الربع الرابع"],"ERAS":["ق.م","م"],"MONTHS":["يناير","فبراير","مارس","أبريل","مايو","يونيو","يوليو","أغسطس","سبتمبر","أكتوبر","نوفمبر","ديسمبر"],"TIMEFORMATS":["zzzz h:mm:ss a","z h:mm:ss a","h:mm:ss a","h:mm a"],"SHORTWEEKDAYS":["الأحد","الاثنين","الثلاثاء","الأربعاء","الخميس","الجمعة","السبت"],"SHORTQUARTERS":["الربع الأول","الربع الثاني","الربع الثالث","الربع الرابع"],"WEEKENDRANGE":[4,5],"STANDALONENARROWWEEKDAYS":["ح","ن","ث","ر","خ","ج","س"],"AVAILABLEFORMATS":null,"NAME":"ar","AMPMS":["ص","م"],"STANDALONEMONTHS":["يناير","فبراير","مارس","أبريل","مايو","يونيو","يوليو","أغسطس","سبتمبر","أكتوبر","نوفمبر","ديسمبر"],"SHORTMONTHS":["يناير","فبراير","مارس","أبريل","مايو","يونيو","يوليو","أغسطس","سبتمبر","أكتوبر","نوفمبر","ديسمبر"],"STANDALONENARROWMONTHS":["ي","ف","م","أ","و","ن","ل","غ","س","ك","ب","د"]}

[Emily Fortuna, 2012/09/04 20:14:42]

nit: can we format these guys more nicely with line breaks so it's not one big
line of text? like:
{
    "DATEFORMATS": ["EEE", "dd/MM/YYYY", etc],
    "NARROWWEEKDAYS":
         ["more weekday names", etc]
}

[Alan Knight, 2012/09/04 23:39:03]

This is the way our JSON library writes things.  I don't really want to format
them manually just to have it overwritten when the data is regenerated. I was
thinking it was sufficient to indicate that the data is exactly the same as that
found in the files this is generated from, where it is formatted more nicely.

[Emily Fortuna, 2012/09/05 01:06:21]

sgtm.