Hide alt values

[movermeyer]

What are you trying to accomplish?

Values in CLDR can have an alt attribute. While we figure out how we want to export them, we should ignore them so they don't accidentally get output.

Ref #125.

What approach did you choose and why?

ruby-cldr had a alt? method that was being used in a few places to ignore these values, but it wasn't being consistently.

I moved the filtering into DataFile, so the rest of the code doesn't even get a chance to see these values, so they can't possibly forget to remove them (thereby leaking them).

What should reviewers focus on?

🤷

The impact of these changes

alt values are hidden and not exported.

Testing

...

Checklist

• I have added a CHANGELOG entry for this change (or determined that it isn't needed)

[movermeyer]

This is not quite right. ruby-cldr already uses alt values in some cases (e.g., narrow-symbol keys in Currencies component).

Perhaps we'll do an allowlist of where we expect alt attributes would be better to know that we are filtering them out appropriately.