The problem is that you forgot a apostrophe after 'jquery-qtip-min)
wp_register_script( 'tooltip', get_stylesheet_directory_uri() . '/qtip-js/tooltip.js', array('jquery', 'imagesloaded', 'jquery-qtip-min), false, true );
should be
wp_register_script( 'tooltip', get_stylesheet_directory_uri() . '/qtip-js/tooltip.js', array('jquery', 'imagesloaded', 'jquery-qtip-min'), false, true );
I know that sometimes you can look over such things, especially if (maybe) you aren’t an experienced coder, but still please try harder next time to spot such really simple typos before posting questions on WPSE.