Added files for swiss german (de_CH). Went for the formal "Sie" (as
opposed to the informal "du" currently used in the locale de).
Suggestion: Allow variants like de_CH@informal and de_CH@formal to make
it possible to be able to offer both, formal and informal addresses for
languages like f.e. german or french and their respective variants.
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Co-authored-by: Ryan Feigenbaum <48868107+royalfig@users.noreply.github.com>
