Added two constants inside Comment class.
Added a private array inside Lookup class.Also, added three methods that are used to manage the array added.
Inside the Post class three constants were added. These are used to store the status of the Post.
The rule method was modified with new rules for the database fields. Also, inside the relations method some changes were made. And two methods wew added inside Post class. One is for normalize tagas and one for retrieving the url of the post.

The Tag class was modified with the addition of two new methods: string2array and array2string