Create a minimal user interface for Exercises for a given User's page

[chubchubcharles]

Now that the backend functionality for CRUD-ing Exercises is available in MongoDB, we should enable users to CRUD on the frontend by creating a user interface.

Task Description: Go on bootstrap and find a neat looking interface for listing exercises for a user profile page. It doesn't have to be fancy. Just add any interface to make it a MVP at least.

Exit Criteria:

• Can Create exercises on another page "/users/:userID/exercises" for users who are logged in.
• Can View exercises on a page "/users/:userID/exercises/" with a list of exercises in whatever format (text, etc.)
• Can Update exercises on the page "/users/:userID/exercises/" by renaming the exercises
• Can Delete exercises on the page "/users/:userID/exercises/"