Added option to configure the UI language per user

[lpaulsen93]

This is an attempt to enable configuration of the UI language per user. Also see forum thread https://forum.dokuwiki.org/thread/16576.

If the logged in user has got a settings in user_settings then that language will be used. Otherwise normal processing continues (...check option use_browser_lang).

Here is a example configuration for user_settings (it is a multi line text field):

UserA="de";
UserB="fr";

So in this example, if UserA logs in, the UI will be presented in german. If UserB logs in, the UI will be presented in french. If some different user logs in or if no one is logged in the plugin will act as before.

[stonier]

This is nice - I wanted to do something like this back when I wrote this plugin, but it was always a nice-to-have. Inbetween myself and my colleagues at work, or my wife at home, making use of HTTP_ACCEPT_LANGUAGE was sufficient.

Alas, I do not have a dokuwiki instance any longer. If you would like to fork this and evolve it for others, please, feel free to do so.