Added migrations and model, and updated Dodont model, such that there is a Category model to which each Dodont belongs
Updated migration and schema
Added an event listener that gives relevant instructions to the dodonts/new page's form based on user selection. Also updated category model and updated dodont model to require a category_id. Finally, added category controller with show action and accompanying route.
Implemented a check for markup in user submissions, and added appropriate tags to user inputs
Made it so that a maximum width of 500px is imposed on images.
Updated to eliminate merge conflict
Merge pull request #13 from fox-squirrels-2013/create_form

Fully implemented guest/user submissions