Modernize the UI by moving to Bootstrap.
Take into account the followin improvements:
- Write the title of grouping boxes (i.e. Burndown, Team's Work, ...) outside of the box. Keep more spacing between the boxes.
- Remove excessive grid from Burndown.
- Harmonize links and buttons in the header bar.
- Clean up Navigation.
- Introduce user portraits to the User Widget and use it to display user activity. Make the online/offline indication graphical, e.g. by a border of the portraint or make the user entry half-transparent. Black-and-white portraits would also be as possibility but are not suitable if user portraits are already black-and-white.
- Move System Messages out of the navigation.
- Introduce a Navigation toggle to the header bar that shows and hides the navigation and lights up if there is activity in the chat.
- Introduce dedicated handles (distinct from the entity id)
8 Story Points