Patch Solr Dist Search - No Stale Check or Nagle

A few weeks ago while benchmarking Yokozuna I found that latency was much higher than I would have expected.  After much investigation I discovered that the Apache HTTP Client (which Solr uses for distributed search) stale check is a large contributor.

* Write an HTTP client for dist search up to spec with the HTTP client version being used.  I noticed currently some deprecated calls are being made.

* Disable the stale check.

* Disable nagle.  The packets being sent aren't small so no need to bother with nagle.

* Change yokozuna build to pull Solr 4.0 source and apply patch files.

* Post benchmarks proving improvement.

* Once settled, send patch to Solr mailing list and jira.