test plan:
* configure an external tool assignment
* add the assignment to a module and require it
to "mark as done"
* as a student, should be able to see and use the
mark as done button when viewing the assignment
closes #OUT-1353
Change-Id: I5dc5ce5a25823f2965bdc9f7b749e4effa7c3576
Reviewed-on: https://gerrit.instructure.com/125363
Tested-by: Jenkins
Reviewed-by: Matt Berns <mberns@instructure.com>
QA-Review: Heath Hales <hhales@instructure.com>
Product-Review: James Williams <jamesw@instructure.com>