comments/possible changes

First off, I should warn you that I'm completely unfamiliar with Cecil. Also IL. And Fody. So any comments may be way off!

Second, the code was a pleasure to read. I understand there are bits still to come, but I liked what I saw. My approach was to read the README.md, then look at the sample Assembly to weave, and those two things gave me a great view. It was easy to picture how the assembly would be used and what would be done to it. 

Then as suggested, I read `ModuleWeaver` and everything just fell into place. It was like reading a story.