v2.4.0

- Dropped PHP 5.6 Support

- Feature: Live Streams
- Feature: Chat for Live Streams
- Improvement: Uploaded videos will now be saved as 'presentation' instead of 'presenter' (to trigger segmentation)
- Bugfix: Workflow Parameters not available for new series
- Bugfix: Fixed Typos
- Bugfix: fetching scheduling of events without scheduling led to crash
- Bugfix: wrong organizers when creating multiple series via internal API
- Bugfix: changed to list view and removed buttons when reloading event list
- Bugfix (skin): dropdown menus in tile view had broken hover effects
- Change: add organizer & contributer only when creating a new series
- Code: Started refactoring the model, made changes for PageComponent plugin