Wiki: Allow instructors to see manually-created sections in the section/group drop-down

See

If an instructor creates manual sections, those sections are not listed in the drop-down. Since there is no option to add an instructor to a manually-created section, they are unable to assign a Wiki page to a manually-created section. Instructors should be able to see all manually-created sections and all groups ( ) in their site even if they have not been added to those sections/groups.