restructure option.xml
fixes several issues
Merge branch 'optionImprovements' of https://github.com/voolia/de.voolia.news into options
Update language variables
Updates language variables
further improvements (WIP)
drop ability to disable rss feeds and fix some issues
handle max count of sources

@pebeah would appreciate it when you test everything so we don't
oversee something :-)
better default value
language improvements
Option improvements
Merge branch 'master' of https://github.com/voolia/de.voolia.news