Added Translations

Added German translations, mainly for the advanced settings page.
#514. Added select2 for time pass categories.
Merge pull request #525 from laterpay/feature/514_category_select_limited

#514. Added select2 for time pass categories.
Closes #514
Merge branch 'master' into feature/452_frontend_improvements

Conflicts:
	laterpay/views/backend/pricing.php