Bug 28762: Use Koha::Course in course-details controller
This patch updates Koha::Course to include the 'instructors' relation
accessor and then update the course-details controller to use the
Koha::Course object and pass it to the template instead of building a
hash using GetCourse.
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com> Signed-off-by: Nick Clemens <nick@bywatersolutions.com> Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>