Change to "standard" directory layout and basic integration with naoutil

I've organized the directory structure to follow the convention used for naoutil. The only difference is that I've left src at the top-level since the code is not embedded within a choreographe project (as naoutil & nao-wanderer are).

I've made some updates so that a NaoEnvironment instance is used to create a Nao instance and the log parameter is optional (if it's not set then python standard logging will be used).

I think the event handling code that Lexa added to naoutil could be used in your event module, but I haven't made an attempt to do that yet as I'm not sure I understand Lexa's code or yours well enough yet.

I've done some basic testing running fluentnao interactively in the python shell connected to a simulator and all seems to work.