code: function isEmpty(value) {
          var classOfValue = classOf(value),
              retVal;
  
          // If value is an array or a string
          if (classOfValue === _Array || classOfValue === _String) {
              retVal = value.length === 0;
          }
  
          else if ((classOfValue === _Number && value !== 0) || (classOfValue === _Function)) {
              retVal = false;
          }
  
          else if (classOfValue === _Object) {
              retVal = isEmptyObj(value);
          }
  
          // If value is `0`, `false`, or is not set (!isset) then `value` is empty.
          else {
              retVal = !isset(value) || value === 0 || value === false;
          }
  
          return retVal;
      }
docs: Checks to see if passed in argument is empty.
  @function module:sjl.empty
  @param value {*} - Value to check.
  @returns {Boolean}