nxdialog / i18n: Make messages localizable (requires gettext for nxagent and nxdialog)

[sunweaver]

Messages issued by NX agent via NX dialog are English only, they need to be made localizable.

[uli42]

So we need to somehow transfer the locale setting from client to server. Is there already some mechanism for that?

[sunweaver]

Normally the language settings are configured in the user session on the remote server. And the same language we should use in NX dialog messages. So nothing to do in that respect, I reckon.