Support type oids
Support type oids

Issue #37 asked for type oids in the output because psycopg2 uses it
directly for internal type manipulation. Although @lionel-panhaleux had
provided PR #38, I didn't like the way it was implemented mainly because
it mixes options. The new option 'include-type-oids' has default to
false. I didn't provide tests for this feature.

fabriziomello/wal2json,eulerto/wal2json