Added lightGallery library. Also added pictures for development
Added some additional styling to the replies#index page
Realized that these views will never be accessed. Deleted its contents
Updated the file size validation. Images must now be greater than or equal to 250x250 pixels
Modified the look of the replies index page. Also added lightGallery to this page
Added gritter gem for non-intrusive notifications
Added gritter error style to posts, users, and replies
Added uniqueness validation to username
Added flash notices to create/edit/destroy. Also added some additional redirects