Returns every string that can be changed, with the wording that currently applies for the
language requested.

Strings that have not been translated into the language return the wording they inherit, so
listing a language you have not used yet returns the full set ready to translate. A string
that has its own wording in this language carries overriding, the wording it would
otherwise inherit.

This list does not take criteria, order or expand, and is not paginated: it always
returns the complete set.