Document how the pillar namespace is flattened.
Trivial doc spelling fix

It is trivial but it is my first commit / pull request so useful for
checking the process is correct. And it has a semicolon
Merge pull request #6343 from go8ose/note-pillar-flat

Document how the pillar namespace is flattened.
Merge pull request #6344 from mikadosoftware/minor-doc-fix

Trivial doc spelling fix