title: What non-negative linear models are supported/planned in scikit-learn?
body: <p>Scikit-learn offers a large variety of useful linear models. However, I am working on a problem which is linear with non-negativity constraints (i.e. solution variables should be non-negative).</p>
  
  <p>I would like to use scikit-learn, but the only function I saw that can support currently non-negativity is Lasso(), via the 'positive=true' flag. LassoCV() or lasso_path() don't support non-negativity.</p>
  
  <p>Are there other non-negative linear models available in scikit-learn? Are there plans to include these in the near future?</p>