title: Set coefficients of an Eigen::Matrix according an arbitrary distribution
body: <p>Eigen::Matrix has a setRandom() method which will set all coefficients of the matrix to random values.  However, is there a built in way to set all the matrix coefficients  to random values while specifying the distribution to use.  </p>
  
  <p>Is there a way to achieve something like the following:</p>
  
  <pre><code>Eigen::Matrix3f myMatrix;
  std::tr1::mt19937 gen;
  std::tr1::uniform_int&lt;int&gt; dist(0,MT_MAX);
  myMatrix.setRandom(dist(gen));
  </code></pre>