Add messages.pot for LaunchPad online translations

[epcim]

I am about to provide Czech translations. This PR just adds po/messages.pot as it is needed for LP translations to discover messages used. Once merged I would switch the main branch on LP to your upstream instead of mine fork.

Question: you are using en_QQ, as probably it is better readable in the terminal for kids. For any translation, I prefer to treat .po files without "spaces" between letters. Can you draft what way we automate the generation of cz_QQ variant? BTW: Not sure if related, but LP offers for English (https://translations.launchpad.net/terminal-quest/+add-custom-language-code) an English code en@quote and en@boldquote.

If you are interested in the LP translations, would be great to add one of our users/emails to the ownership of the LP project I started.

See more here: https://translations.launchpad.net/terminal-quest

[epcim]

@carloseduleal @Ealdwulf any interest?

[Ealdwulf]

Hi, thanks for this. We don't normally check in messages.pot, as it is an autogenerated file. Does LP really need it checked in?

Regarding en_QQ, we don't use that for readability purposes - it exists to allow English-speaking testers to spot internationalisation failures (strings not marked as translatable, wrapping failures, etc). We weren't anticiapting using it as a UI feature. Do you find terminal quest not sufficiently readable? That wold probably be better addressed in the GTK CSS.

[epcim]

Hi, well messages.pot is required by LP (you may one load by file at the beginning) but having it in repo - it is processed automatically, the same for updates I guess.

Ok, let's forget my question to _QQ, not important I count to deliver cz.po

Questions not answered:

1. Will do you tend to merge messages.pot based on the above?
2. If you are interested in the LP translations, what users/emails I should add to the ownership of the LP project I started (so you can control it in future).