Change: for surveys capture more information about the OpenTTD version

[TrueBrain]

Motivation / Problem

While working on #11232 @glx22 mentioned that the "newgrf_version" in decimals wasn't all that useful. And that the content-version would be more useful, but we didn't add that yet.

While looking into that, I also noticed we don't even tell when a version was tagged, or which exact hash it is.

Description

Address these issues all at once, and put them in a new version object. This means we now have all kinds of information about the OpenTTD version that was used for the survey.

The hash is always uniquely pointing to a single commit, so good to deduplicate on
The revision is the human-readable variant of hash.
The tagged and modified tells us if we should trust the survey result to begin with.
The newgrf and content gives us a rough estimation what kind of client it is, if it isn't a stable release. Not the most useful piece of information of this blob, but it might be useful some day.

Limitations

Checklist for review

Some things are not automated, and forgotten often. This list is a reminder for the reviewers.

• The bug fix is important enough to be backported? (label: 'backport requested')
• This PR touches english.txt or translations? Check the guidelines
• This PR affects the save game format? (label 'savegame upgrade')
• This PR affects the GS/AI API? (label 'needs review: Script API')
  • ai_changelog.hpp, game_changelog.hpp need updating.
  • The compatibility wrappers (compat_*.nut) need updating.
• This PR affects the NewGRF API? (label 'needs review: NewGRF')
  • newgrf_debug_data.h may need updating.
  • PR must be added to API tracker