Add Setting for per-language Tab display if WPML is present

[jevgen]

On single tab setting UI there is "Translation Priority" selector via search, that does not make much sense. Instead it would be much more useful to have "Select language with which this tab will be displayed" with drop down or flags selector of languages defined in WPML.

Even more universal would be a string setting with custom logic, which would also allow input of ICL-LANGUAGE parameter, like Widget Logic plugin does for normal WP widgets.

[kpu23]

We need the WPML team to work with us on this front. We don't want to add functionality into our plugin that relies on specific WPML code. Rather, it should be a coordinated effort so we know it's not going to break in the future.

We're awaiting a reply from WPML.