Added British English as a locale
Basically, I've added the most common variety of English used outside of The United States. Mainly in Europe. Did it because it's kind of uncomfortable to switch your theme to EU, while the English is still as American as it gets.
Not sure if I've missed a spot. I've even manually modified the .defconfig files just in case.
While we're at it, could you check up on my request for the Theme as well? Changed the "Favorites" SVG into "Favourites" basically.