Merge pull request #167 from danirod/master

Bump Ubuntu version in README
Use Logger::tr instead of QObject::tr.
Update translations.
Update makefile.
Backport some changes from record-schedule branch to fix a bug.
Update translations

Greek (ελληνικά) language
Merge pull request #175 from NikTh/master

Add Greek translation.
Add German and Greek translation to the build system.
Added more german translations
Merge pull request #176 from sysms/master

Added more german translations
All translations except "logger" done.
fixed german translations, started translations for "logger"
Merge pull request #181 from sysms/master

All german translations (except "logger") done.
Adding sudo command on debian
Update AUTHORS.md.
Merge pull request #185 from michelwilhelm/master

Adding sudo command on debian