This is some preliminary refactoring related to a pending patch
to allow sepgsql-enable sessions to make dynamic label transitions.
But this commit doesn't involve any functional change: it just puts
some bits of code in more logical places.
KaiGai Kohei
This is still pretty rough - among other things, the documentation
needs work, and the messages need a visit from the style police -
but this gets the basic framework in place.
KaiGai Kohei