work in progress: new project template

This is just a work in progress that probably isn't ready to merge yet, but I wanted to see what you thought.

I've added a `newproject_copy_me` folder with the basic files needed to create a new book and readme document (`README_new_book.rst` - see [here](https://github.com/isaacdontjelindell/runestone/blob/newproject-issue-206/README_new_book.rst) for a rendered copy).

I opted to add a separate pavement file in that directory to make it easy to build a new book - let me know if you can think of a better way of doing it.

What am I missing?