title: Project on multiple fields in C# MongoDB 2.0
body: <p>How do you project on fields in the new MongoDB C# drivers when the fields are given in the form of a String array ?.
  I could find ways to project on a single field by doing </p>
  
  <p><code>collection.find(filter).Project(Builders&lt;Category&gt;.Projection.Include(fieldName)</code></p>
  
  <p>How do I extend this to take an array of fields ?.</p>