Add breadcrumbs and header elements, refactor routes, link restaurants to restaurant reviews page

[oxyflush]

This MR:

1. Refactors existing app.js routes. This is done primarily to place them in a more common, cleaner file that is able to reuse and export constants that will be needed for other elements.
2. Adds breadcrumbs from reactstrap and header elements to the restaurants page. These elements pull from the routes.js file that specifies aliases for some pages and provides emphasis on active breadcrumbs with links on the inactive ones.
3. Provide a link to restaurant review page for each restaurant.

Addresses https://github.com/NickPriv/FryRank/issues/18