This ought to get rid of the cycles < 10000 queries observed with some
seed values.

Dumps ASTs in graphml.  Available via --dump-all-graphs.  Stylesheet
to turn it into graphviz included.

This eases piping to a postgres process.

Now logging target conninfo of instances.

Schema is now reachable via scope and no longer a statically
initialized object.

Regression: Timing information has been lost.