A teacher can set a wiki to be collaborative or individual

1. Login as a teacher and create two wikis, one set to collaborative and one set to individual.
2. Edit the first page of each wiki and save.
3. Login as student1, access the collaborative wiki and check that you can view the first page created by the teacher and can edit it.
4. Access the individual wiki and edit the first page.
5. Login as student2, access the individual wiki and edit the first page.
6. Login as the teacher, access the individual wiki and check that you can view the pages created by student1 and student2.