Don't use Intl until Fx30, since it's missing in Iceweasel 29

And nsICollation isn't broken on OS X until 30
Fix for startup error w/weird locale language tags ("de-CH@currency=EUR")

https://forums.zotero.org/discussion/37901

And just return a noop sorter on failure instead of breaking
Update version
Merge from upstream 4.0