Improve German translation
I figured that improving the translation would help a few folks, mainly older lifters.
Fixes several of the following:
- Orthographic problems
- Mistranslations (most notably, using "Gesamt" as the column name for the total)
- Country names
There are still a lot of things left to be fixed for country filters, i.e. "all country-ish lifters", but I'll leave that for another time.