elasticsearch/elasticsearch — pull request #7187 by uboness (2014-08-07 10:53:03+00:00)
Title: Added transient header support for TransportMessage

- Transient headers are headers that can be set on messages yet are not serialized with them.
- Changed header accessors/mutators so header manipulation will be done directly on the request (to void NPE with transport message headers when dealing with maps that can potentially be null)
- Added a randomVersionCompatibleWith(Version) method to the test infrastructure to help with bwc testing