Refactored form code into partials
added URL format check in Picture model
added confirmation message for delete method
Added 'copyrighted' attribute to model
Added scope for 'free' and 'alphabetical' parameters
added some buttons on index page
modified gemfile for heroku
modified css and index page
resolved conflicts
Added Ajax for upvote/downvote buttons
Modified index page, changed upvotes/downvotes text to likes/dislikes