Start of modals.

 On branch master

	modified:   public/index.html
	modified:   public/scripts/main.js
	renamed:    public/images/social_button_sprite.jpg -> public/stylesheets/images/social_button_sprite.jpg
	renamed:    public/images/social_button_sprite_hover.jpg -> public/stylesheets/images/social_button_sprite_hover.jpg
	modified:   public/stylesheets/main.css