Fixes/internationalisation on mobile devices

includes a fix to find the more general i18n file if a subregion has been specified. For example if the user agent send requests  with `pt-PT` the client will try to load language `pt.js` if `pt_PT.js` is not found.

**Note** 
Javascript notations refuses to declare `i18n.pt-PT` so the implementation converts language strings to `pt_PT`. The according language file has to be named appropriately (and of course to be added as `jsSourceFile` in the `pom.xml`)