Log Message:
Update thin to 1.6.4.

== 1.6.4 Gob Bluth
 * Increase REQUEST_PATH to 2048 symbols [X2rdas]
 * Fix warning in logger [tenderlove]
 * Add :timeout option for Rack::Server.new [sugitak]
 * When restarting, exit on a next tick so we can send response back to a client \ 
[rsamoilov]
 * Check for empty PID files [z1dane]
 * Update Event Machine version to 1.0.4, Ruby 2.2.0 fix [freemanoid]