Unicorn 4.4.0 - Rack HTTP server for fast clients and Unix

Unicorn is an HTTP server for Rack applications designed to only serve
fast clients on low-latency, high-bandwidth connections and take
advantage of features in Unix/Unix-like kernels. Slow clients should
only be served by placing a reverse proxy capable of fully buffering
both the the request and response in between Unicorn and slow clients.

Changes:

Non-regular files are no longer reopened on SIGUSR1. This
allows users to specify FIFOs as log destinations.

TCP_NOPUSH/TCP_CORK is no longer set/unset by default. Use
:tcp_nopush explicitly with the “listen” directive if you wish
to enable TCP_NOPUSH/TCP_CORK.

Listen sockets are now bound after loading the application for
preload_app(true) users. This prevents load balancers from
sending traffic to an application server while the application
is still loading.

There are also minor test suite cleanups.