Merge pull request #25 from whoisglover/assignments_show

Assignments show - partially complete
work in progress commit, setting up routes, controller, and tests for feedback
quick fix for seed/factories for submissions

This is not a permanent fix.  This commit adds a user_id to the submission factory so seeds can happen and routes can be viewed.  This should be done dynamically in the future.
added table to assignment overview.  Still needs links and logic to submissions page.
Created model, controller, route for feedback.

TDD for feedback create and index route.  Index provides all feedback for a given
submission.  If no submission id is provided no feedback is returned.  Create allows
teachers to create feedback for a given submission.  Feedback can only be created by logged in teachers.
Again no feedback is created without a submission id.
Merge pull request #26 from whoisglover/feedback_routes

Feedback routes
cleaned up views - switched lists to tables
Fixed view issues