Implement logging library

[Th0ught09]

I noticed a lot of the code makes use of the error function, I think these would be better replaced by the logging library. It's something I've worked with before and would like to try it again :)

[olivierpierre]

Sounds like a good idea. Here we also have then function warning, info and debug which I assume the logging library could replace too.

[Th0ught09]

Merged with #34