Document how users can select the locale of their choice for all supported containers

+++ This bug was initially created as a clone of Bug #1002303 +++

Description of problem: We intend to localize all UI's in the 5-6 languages that most of our customers prefer. With much of the translation work complete, we need to apply the translated content to our product builds and provide an interface for the users to pick the locale of their choice.

Attaching an EAP example screenshot.

— Additional comment from Rajesh Rajasekaran on 2013-09-06 16:20:05 EDT —

Setting target milestone to ER4 since we need to tacke this soon.

— Additional comment from Rajesh Rajasekaran on 2013-09-25 06:28:40 EDT —

From David:

Now, it's possible to install the app in one of the 7 supported languages.

To figure out how language selection works, please read here: https://github.com/droolsjbpm/jbpm-dashboard/tree/master/jbpm-dashboard-distributions/src/main/jbossas7#languages-supported

Shared features (both business-central and dashbuilder):
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1.- Auto-detect the language from the client browser.

2.- Support for the following 7 languages: English, Spanish, Japanese, Chinese, Portuguese, French, German.

Dashbuilder only features
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3.- Ability to change the preferred language from UI.
(I guess business-central is going to add this feature soon).

4.- Ability to set either the available languages and the default system language on installation time. Via Java system properties.
(I guess this might also be a nice-to-have feature for business-central).

As for Tomcat support, as far as I know, there are no reported issues.

My opinion is that in order to close the related BZ 1002303, we should implement #3 & #4 in business-central (i.e: Uberfire) but that's something it's not up to me to decide.