title: Use all cores to train ANN via neuralnet
body: <p>I am training ANN via package neuralnet in R and the problem is that it uses only 1 core in the training process. 
  I've installed package parallel and I've tried to use something like</p>
  
  <pre><code>nn&lt;-doParallel|parallel and so...(neuralnet(formula,.....)
  </code></pre>
  
  <p>but I am not wel skilled in these issues.
  Any advices to how to let all the cores work during the training process to make it faster?
  If I use</p>
  
  <pre><code>detectCores()
  </code></pre>
  
  <p>It sees all 4 cores.</p>