title: Project attributes on local secondary index with DynamoDBMapper
body: <p>I am using DynamoDBMapper to interact with DynamoDB and would like to project non-key attributes to the local secondary index that I have defined. </p>
  
  <p>How do I define the projections in the model class? The annotation for secondary index does not have any property that would let me. I am not able to find any documentation anywhere.</p>
  
  <p>Thanks,<br>
  Shrikant</p>