#1073 NumberFormatter + DateFormatter need to support a ThreadLocale for report generation

[jfirechief]

DO NOT EDIT OR ANSWER THIS ISSUE. SEE THE ORIGINAL ISSUE INSTEAD:
https://www.jfire.org/modules/bugs/view.php?id=1511
ORIGINAL REPORTER: marco

Both, the NumberFormatter and the DateFormatter use the settings of the current user. But in report generation, there should be a possibility to render the report in a different formatting (e.g. when generating an invoice for an English-speaking customer). Therefore, the NumberFormatter as well as the DateFormatter should provide some ThreadLocale-based API which can be used by the report engine to force a certain language other than the user's language.

[jfirechief]

ORIGINAL COMMENT BY marco, VIEW IT HERE:
https://www.jfire.org/modules/bugs/view.php?id=1511

The NLLocale provides this API now, since both formatters and many other things use the NLLocale and forcing a certain Locale should therefore be done there.