title: Slick Init - slickPause undefined
body: <p>When trying to pause the slider within the init listener the <code>slick('slickPause')</code> method doesn't work with the error</p>
  
  <blockquote>
    <p>Uncaught TypeError: Cannot read property 'slickPause' of undefined</p>
  </blockquote>
  
  <p>An example piece of code is: </p>
  
  <pre><code>var opts = {
              autoplay: true,
              autoplaySpeed: 5000,
              speed: 750,
              fade: true,
              arrows: false,
              appendDots: $('.nav-wrap div'),
              dots: true,
  };
  
  $(elem).on('init', function(event, slick){
              var slider = slick.$slider;
              slider.slick('slickPause');
  });
  
  $(elem).slick(opts);
  </code></pre>
  
  <p>It seems there should be a ready event but there isn't, any idea on how to get around this?</p>
  
  <p>The purpose of needing this is to detect if the first slide is video, if so pause the slider and play the video and then continue. </p>