Updated Posts and Categories verbose name, added migration
Added fields views and likes to the models Posts and Category. Added
function to return the field many to many relationship field categories.

Overwritten the save method, to update the slug field to be equal to the
title.
Displays a column with the list of categories each post is associated
with in the admin area.
Updated settings.
Added category function that returns all the posts associated with the
category that has been passed in the url (category_name_slug).

Updated index function to return only the categories that are associated
with posts, other than returning all the categories in the system.

Updated app urls
Updated base and index templates, added category template