Add locheck run script to Riot target.

[pixlwave]

This PR makes 2 changes to the project:

1. A pre-build script will now run locheck to validate all lproj localisations against en.
2. Removes all strings that are in the project which fail this validation.

As locheck is only available through Mint, the installation instructions have been updated, and I've added a Brewfile containing this dependency along with Xcodegen.

[github-actions]

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[pixlwave]

Note: I’m not exactly sure why this happens to happen when ran the script to clean the strings, but Pirate is an excluded language from the project anyway, so personally I’m not convinced there’s too much to be worried about here. Happy to tidy it up manually though if that’s a better idea 🙂

[aringenbach]

This works well for me 👍

Just a small conversation starter on Brewfile contents.

[aringenbach]

I noticed this, was wondering if it was a good or bad thing. At the moment I'm feeling that this is a good thing since this can help us notice if we're not in sync with everyone else on XCode/macOS versions.

Still pointing this out for other people thoughts on it :)

We have to be careful what changes we commit for this file though

[aringenbach]

Actually this field is not empty for me as well, I don't think it's a problem, but it would be better to know what it does.

[pixlwave]

Command line tools version? I know I don't have those installed atm.

[aringenbach]

Oh yeah that's why it's empty for you then. It's probably only informative anyway (in our case at least).