Clogger 0.0.2 - configurable request logging for Rack

Clogger is Rack middleware for logging HTTP requests. The log format
is customizable so you can specify exactly which fields to log.

The $request_uri variable (as documented in the README) is now
implemented. Those using C extension could potentially segfault
if the app returned an invalid response; we now log 500 errors
in their place.