Mostly grenade documentation

I added some information in the g1 file, and in the file that describes the grenade section. I also added a table header in the g1 file, and I changed the subsections in that file to use dashed headers (`-----`).

Finally, I also added a README.Md. I just fealt that one was needed for the sake of completion :P

Apparently this thing supports emoticons: :+1: :coffee: