Expand Chapter 1 with tree of grammar, features and references

Hi Peter

After a bit of a struggle with github, here's what I've done:

I created a fresh repo in github as a copy of your marpa-guide, and then on my laptop.

On the laptop I created a branch called b.1, and put in that all my previous work. I'll work in b.1 hereafter.

So, if you have a copy of the previous branch ron.savage, please delete it.

Cheers