Implement fastlane step 1 - minimal framework

[SomeTroglodyte]

This just might close #6587. Perhaps. Almost no idea how to actually test (I could merge into my master then fake a few commits for a changelog then go through the steps to trigger a version 701 there, just to see the script creating a file, but that's a lot of work, especially getting my master back into sync. Testing the F-Droid side by forking their server code and setting up my own f-repo is even more disproportionate).

Done

• Minimal required fastlane structure
• Coded generation of changelogs/*.txt discrete files (this guide lists them as 'nice to have', but I think their importance is higher)
• Made sure image sizes match recommendations where any can be found (192² for icon, 1024x500 for featureGraphic, both already available)
• Fulfill requiremets to make it into the "Latest" spam as per this

To-Do after this PR

• File a PR against Unciv's fdroiddata yml to remove Description entirely (it overrides fastlane, all languages)
• Automate syncing android/res/drawable-xxxhdpi/uncivicon2.png to fastlane/metadata/android/en-US/images/icon.png (In that js script? Copy or symlink?)
• Automate syncing extraImages/Feature graphic - Google Play.png to fastlane/metadata/android/en-US/images/featureGraphic.png
• Automate syncing extraImages/Screenshots to fastlane/metadata/android/en-US/images/phoneScreenshots
• Place hooks into template.properties to ask for translations for the full_description.txt and short_description.txt files
• Automate copying these translations into the fastlane structure (In TranslationFileWriter?)

P.S.: I snuck in an updated "MapEditor" phone image. I opted for an Europe map and the View tab.

[JackRainy]

It seems the content of full_description.txt in de and en-US are swapped.

[SomeTroglodyte]

Not only swapped, Notpadqq somehow used an encoding Studio didn't like, so I let it choose.

[yairm210]

I separated this logic into a separate fine precisely so it could be run with node locally :)

[xlenstra]

Is it intentional that the en-US/full_description.txt is now empty, while the same file for de/ does contain the full description?

[SomeTroglodyte]

separate fine

fine as in pay money for some transgression?

now empty

What??? I had them open side by side and AS in such a case even cleverly prepends enough path to distinguish them - should be impossible to fumble...

[SomeTroglodyte]

The PR for the first to-do item is here - a major PITA to create that on gitlab. The direct edit persistently refuses any changes "someone else was faster than you" (impossible to be always the case), and the web IDE takes up to 5 minutes for each and every tiny step.... I have no idea how to deal with that "fast-forward merge is not possible", though. Rollback - too many unrelated mails from their gitlab bot. Update: Our friend linsui did it just now.