Course role switch: add other roles as well

Since 15.0 users can select the role in the course to determine what functionality they want to use. The implemented roles are owners, coaches and participants. 

In reality the system offers many other roles that are not yet visible in that menu. 

Todo:

• Assigned curriculum roles
  • master coach (read-only)
• Assigned organisation roles
  • Administrator
  • Learning resource manager
  • Principal (read-only)

When entering the course the cascade of preselecting the roles is as follows: 

1. owner
2. administrator
3. learning resource manager
4. coach
5. principal
6. master coach
7. participant