dist/u.packed.js
function(duration, callback) {
      return this.each(function(index, el) {
        u(el).scrollTo(0, duration, callback);
      });
    }
function(duration, callback) {
      return this.each(function(index, el) {
        u(el).scrollTo(0, duration, callback);
      });
    }
function ( duration , callback ) { return this . each ( function ( index , el ) { u ( el ) . scrollTo ( 0 , duration , callback ) ; } ) ; }
scrollToTop method
shortcut for scroll to 0
@param  {number}   duration - duration for the animation
@param  {function} callback - function to call when finished
@return {object}   this
scrollToTop method shortcut for scroll to 0