Adding an index on a column in entity framework

Adding an index column in entity framework was not easy until entity framework 6.1. Today (6/20/2014) the entity frame 6.1.1 got released officially. I just downloaded through nuget package manager in visual studio 2013 and liked the simplicity of doing this job.   I am surprised that the EF6.1.1 has been downloaded so many times on the first day. it shows how popular it is.

  [IndexAttribute]
 public string ZipCode { get; set; }