title: async.waterfall inside async.each doesn't work?
body: <p>I'm trying to run an async.each over an array of items.</p>
  
  <p>For each item, I want to run an async.waterfall.   See code below.</p>
  
  <pre><code>var ids = [1, 2];
  
  async.each(ids, 
  
      function (id, callback) {
  
          console.log('running waterfall...');
  
          async.waterfall([
  
              function (next) {
  
                  console.log('running waterfall function 1...');
  
                  next();
              },
  
              function (next) {
  
                  console.log('running waterfall function 2...');
  
                  next();
              }],
  
              function (err) {
  
                  if (err) {
                      console.error(err);
                  }
                  else {
                      console.log('waterfall completed successfully!');
                  }
  
                  callback();
              });
      }, 
  
      function (err) {
  
          if (err) {
              console.error(err);
          }
          else {
              console.log('each completed successfully!');
          }
  
      });
  
  return;
  </code></pre>
  
  <p>The output for this code looks like:</p>
  
  <pre><code>running waterfall...
  running waterfall function 1...
  running waterfall...
  running waterfall function 1...
  running waterfall function 2...
  running waterfall function 2...
  waterfall completed successfully!
  waterfall completed successfully!
  each completed successfully!
  </code></pre>
  
  <p>But my intention is and my understanding is that the output should look like this:</p>
  
  <pre><code>running waterfall...
  running waterfall function 1...
  running waterfall function 2...
  waterfall completed successfully!
  running waterfall...
  running waterfall function 1...
  running waterfall function 2...
  waterfall completed successfully!
  each completed successfully!
  </code></pre>
  
  <p>I keep looking over the code and I don't know what's wrong, does anyone know if my code or my expectations for what the async methods should be doing is incorrect?</p>
  
  <p>Thank you!</p>