The stream limit_req module rate limits incoming connections in the stream
subsystem.  limit_req_zone and limit_req are spelled and counted as in the
http module, burst, nodelay, delay and the dry run included, so a rate
written down once reads the same for TCP, UDP and HTTP.  The handler runs
in the preaccess phase, so a refused connection is closed before anything
is proxied.

This port only installs the module sources.  The module itself is built by
the nginx ports when their STREAM_LIMIT_REQ option is enabled.
