Shain/client logger

:construction: Still some things not quite fleshed out, but a good starting place.

Basically, this proposes a new logging framework/style that retains backwards compatibility (if needed) and allows a simpler, more modular approach to creating and configuring loggers for the chef client. Also included would be some new loggers giving native support for syslog (finally!) and Windows (covered in a separate RFC)
I really like this approach. On the other hand, the default (if no loggers were specified) would be a fallback to using MonoLogger initialized at runtime with STDOUT etc. If you want to disable the loggers I believe you'd just say loggers [ ].

That being said, I like this way better.