Linked some of the pages together

-added some links on the homepage (that take you to the restaurant page
for 5 restaurants)
-added 'add a review' button to the restaurant page (that links to the
'add a review' page with the correct restaurant id)
-'submit review' button added to the 'add a review' page (this button
takes you to the 'add a review was successful!' view for now)