Nr task modal fix

The content of the modal is reformatted.
The close button is removed.
Edit/save and delete buttons show up before the task is started only for the author and PC. 
Hire button always(before and after the team runs) shows up only for the author and the PC. 

Start button and complete button are merged. 
Start button only shows up after the task is started.
When the task is started, the start button changes to complete button. 
When the task is completed, the complete button is disabled.

How to test:
1. Check if the formatting of the modal content both in edit mode and display mode has any issues.
2. Create a task with 2 members. Set different roles (PC and worker) for each member.
3. Check the buttons on the modal in all views based on what is explained above.
4. Start the team and check the buttons on the modals.
5. Refresh the page and check the buttons on the modals.