title: Custom sorting for lucene
body: <p>I have document with fields like (title, content, datetime)
  I want to sort the results with the following formula</p>
  
  <p>1) title boosts 2.5</p>
  
  <p>2) content boost 1.5</p>
  
  <p>3) IMPORTANT (boost those documents that is newer means datetime field is near today date) boost 3</p>
  
  <p>how can I write a query considering the above criteria
  what should I do for #3</p>
  
  <p>any help would be greatly appreciate.</p>