Allow students to view individual details about an assignment

[s-espinosa]

Each of the assignments from #17 should lead to a show page for that assignment.

Each assignment show page should allow a student to submit a link to their project repository (and potentially a link to their project in production?).

If the project has been scored by an instructor, the scores should show here as well.

If the project has not been scored, the page should display a rubric.