make sure `code` is defined
pep8: "is None"-checks
fixup "more python3 compatibility"
rm fintl code
switch magic implementation
fix alsaaudio dependency
refactor playlistitem metadata
define global app variable

this mainly avoids flake8 errors
mv i18n files
add babel to setup
include pot file
normalize i18n date formats
update catalog
update german translation
split headless baseclass from input