Merge pull request #11 from SimpleReviews/prod-reviews

updated product template
added navbar and a main app view
Merge branch 'feature/nav'
fixed product template
minor fix
fixed columns div
Fixed the category api

- A product's category is now set based on the product selected from the Semantics3 api.

Closes #12
Merge pull request #14 from SimpleReviews/fix/categories-api

Fixed the category api
review updates
template update