[Feature]: Add default `-Duser.language` and `-Duser.country` java-options to MapTool.cfg

[FullBleed]

Describe the Problem

There is no obvious way to change the language that MT uses without changing one's default OS language.

The Language selector inside Preferences>Startup is non-responsive (like all settings there) but it does point to the .cfg file to make changes. But when a user goes to the cfg file it's not clear what would need to be added or modified to change the language.

The Solution you'd like

Add default -Duser.language and -Duser.country java-options to MapTool.cfg.

If they could see the current language and country options, it would be more obvious what needed to be done.

Alternatives that you've considered.

Rely on Wiki, Forums, or Discord to relay the info--But there is no reason this shouldn't be more visible in-app.

Additional Context

It would also be nice if there was some text under the Language selector (in the Startup tab in Preferences) that specifically instructed what java-options needed to be changed.

[kwvanderlinde]

I'm not sure if this is feasible. The list of options is whatever gets provided at build-time (when we don't know the locale to use) and I don't think there's a way to set these options with a value that says "use the system settings". Happy to be corrected on this, of course.

[FullBleed]

Too bad.

Maybe just add java-options parameters to the preferences>startup tab then?

In fact, all of the entries in the Startup tab could be updated with their respective java-options (perhaps in a 4th column).

[bubblobill]

@FullBleed fear not, @kwvanderlinde is wrong.

In build.gradle I changed

def javaArgs = [
        "-Xss8M",
] + mo...

to

def javaArgs = [
        "-Xss8M",
        "-Duser.language=" + "und",
        "-Duser.country=" + "",
] + mo...

In my build folder, MapTool-Dev-Release.cfg I now have the lines

java-options=-Duser.language=und
java-options=-Duser.country=

I am not brave enough to commit such a fiddle, so someone who knows what they are doing will need to make the change.