Add a rough OSM I/O graphing code example.
Add a rough OSM I/O graphing code example.

This is the code I used to produce graphs during my last presentation,
"Speedrunning the Open Street Map osm2pgsql Loader", recorded during
Crunchy's PostGIS Day 2022 on Nov 17.
Slides:  https://tinyurl.com/2v7ctrp5 and public video will follow.

gregs1104/pgbench-tools,gregs1104/pgbench-tools,gregs1104/pgbench-tools