title: postgres 9.4 and unicode in json
body: <p>I've ended up with some json data imported into the database which contains unicode escapes in the json key. And I can't seem to find a way to address the data. The simplest example is:</p>
  
  <p>select '{"test\u0007":123}'::json->'test\u0007'</p>
  
  <p>Instead of getting 123 back, I get NULL. Can anyone help?</p>