Optimization: Store node children as node attributes
Optimization: Store node children as node attributes

* This saves having a dictionary per for node with any child,
  even just one.

* Memory usage goes down by 6% doing this.

* This will also allow more direct access without going through
  accessor functions.

kayhayen/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka