Fixed #1260 (Change description of percent base choices)
Merge pull request #1262 from emanuelschuetze/fix-1260-1261

Fix for new percent base choice config (Fixed #1260)
Updated English language file.
Merge pull request #1269 from normanjaeckel/Translation

Updated English language file.
Updated CHANGELOG, README.rst, requirements files, .travis.yml and setup.py.