Add German translation and fix minor issues

[drodenkirchen]

• Adds German translation of README
• Adds link to german README to other READMEs
• Remove unused imports
• Correct doc string on stream reading segment that reads new token, not server name
• Add additional info on Exception that fails on not being able to load the size of both data sets. (They are read consecutively, without a seperate check for WearingsSize)