Add more notes.
Rename goj.go to decoder.
Work on docs and which methods are exported.
Add Val type.
Remove Val

I want people to be able to get the plain interface back.
Add comment.
More cleanup.
Rename types file to path_types.
Dont export Branch type.
Add start of toplevel docs.
Add PruneBranches.
Clean up PruneBranches.
Remove v from path.
Add docs.
Move copyZero function.
Remove commented out logger.
Pass path directly.
Clean up leaf.
Update comment.