Adding German (Switzerland), English (UK) locales

And I've fixed some missing hyphens in the German one as well.

The idea behind the en-GB locale is to make apps work that set I18n.locale to en-GB. The same could be done for en-CA and other English locales, even if no words currently diverge betweeen those.

Otherwise, if these locales are missing, applications setting them will find "translation missing" errors in their ActiveAdmin panels.

The de-CH locale file is there because German in Switzerland does not use ß, and the de.yml file contains the word "Größer".

No failing tests here (I would hope so!) :)