Add Hungarian translation

[flaktack]

Summary

This adds a Hungarian translation, along with a few translations changes:

• the debug client translation files are regenerated, a few missing texts are enclosed with _tr()
• Origin/Destination texts are added to internals.properties so those may also be translated
• add LOCATION_NOT_ACCESSIBLE to Message.properties
• correct locale date/time parameter handling in the debug client

Issue

#3840

[flaktack]

@debyos thanks for the translations. I've looked through the source code, and there were two more files: could you also create translations for these too?

[flaktack]

I've translated the missing parts -- this is ready for review.

[leonardehrenfried]

There a quite a few strings that now have an empty string. Will they fallback to a default locale or really show the empty string when used?

[flaktack]

It will fallback to the default value if no translation exists for both the java and javascript translations. I've updated the code to remove the untranslated defaults from the property files.

Currently the Message.properties (trip planning error/status message translations) isn't used -- should I change that here or will that be fixed as part of the itinerary refactors?

[leonardehrenfried]

This is probably from #3908, isn't it?

[flaktack]

Yes, I rebased onto the wrong branch. I've removed those commits.