WIP: Swissgerman Translation

I translated Pleroma into swissgerman. I pulled most of the wording from the already existing german translation to be (hopefully) inline with Pleromas wording in gerneral.

Sadly there is somewhat of a problem: the "code" for the language is "de-ch" and pleroma handles language-codes, such as this one, in an inconvenient way.

It splits them at the "-" and only uses the first part, as can be seen in the main.js:

const currentLocale = (window.navigator.language || 'en').split('-')[0]

Which is why I labeled this merge-request as WIP.

I have no clue how to get that stuff sorted out in a way that is pleasant to you guys.

So pwease help me getting this glorious and highly needed translation into pleroma! (´・ω・`)