Added Flask-restful module

Updated user profile test to use fixture
Added /users/<username>/sets route.
Included API doc in the index page.
typo
Fixed documentation
Renamed tests.
Added inventory test.

Added is_textless, is_promo and is_signed fields.
Implemented /cards/<string:cardname>/ method.
Refactored api doc rendering in JSON/HTML.
Added a Try-it button on homepage.