Update language-data from upstream

[ToluAyodele]

Add Saho (ssy) and Western Pwo (pwo)

Updating to wikimedia/language-data@637511d

[amire80]

This patch mixes two things: Adding new languages and updating unrelated things from CLDR upstream.

Please follow the instructions in https://www.mediawiki.org/wiki/Manual:Adding_and_removing_languages#language-data :

1. Run the updating script before adding the new language.
2. Get that updated reviewed and merged.
3. Add the new language.
4. Run the updating script again.

[ToluAyodele]

This patch mixes two things: Adding new languages and updating unrelated things from CLDR upstream.

Please follow the instructions in https://www.mediawiki.org/wiki/Manual:Adding_and_removing_languages#language-data :

1. Run the updating script before adding the new language.
2. Get that updated reviewed and merged.
3. Add the new language.
4. Run the updating script again.

Yes, the changes made from the script( ./scripts/fetch-language-data.sh) being run the first time is what was included in this PR. It included changes from CLDR upstream and the new languages being added all in one

[amire80]

Oh sorry, I'm sometimes an idiot, I thought that it's the language-data repo. It's good to go.