Update translations.php

Added some more Swedish translations.
Add Task CSV export and Kanboard CLI
Add CLI documentation
Improve webhooks to call external url on task creation/modification
Update JSON API documentation
Improve german translation (merge pull-request #185)
Overdue date have a different color now (merge pull-request #186)
Minor css change
Fix bug: wrong date displayed by strftime (#178)
Update translations.php
Added Finnish translation
Add contributor
Update chinese translation
Update Ubuntu installation doc (merge pull-request #198)
Project cloning/duplication (pull-request #196)
Add ReverseProxy authentication (pull-request #199)
Add new contributor
Merge pull-request #188 (update translations)
Add new contributor
Add Reverse-Proxy authentication documentation (pull-request #202)