The enterprise ID of this CourseSection. CourseSections that model Sections from
the CM service have enterprise IDs. Manually created CourseSections have an
EID of null.
The enterprise ID of the Section that this CourseSection models.
Gets the maximum number of enrollments allowed in this CourseSection.
Instructors and TAs may assign more than the maximum number of enrollments,
but students may not self enroll in a section at or above the maximum
number of enrollments.