jQuery(...).addClass(...).viewportChecker is not a function
<p>Context: I'm using a theme with a lot of custom JS that was all working until I started adding my own javascript, at which point I started getting this error: </p>

<pre><code>theme.js:28 Uncaught TypeError: jQuery(...).addClass(...).viewportChecker is not a function
</code></pre>

<p>The line it's erroring on is the following:</p>

<pre><code>jQuery('.scroll1').addClass("hidden").viewportChecker({
    classToAdd: 'visible animated fadeIn', // Class to add to the elements when they are visible  
}); ; 
</code></pre>

<p>At first I assumed jQuery was updating their libraries, but as the issue is still persisting this morning... I do not believe that is the case. </p>

<p>link for assistance is <a href="http://yardlad.webbtechgroup.us" rel="nofollow">http://yardlad.webbtechgroup.us</a></p>