Russell Owen, this is the bulk of my changes to remove version=0 tables. It sits on top of changes from DM-2533 and DM-2534 in some packages, with more changes on DM-2536 yet to come. I'm getting them all reviewed separately, but I'll merge them all together, which is why you may see some unit tests skipped in what I've asked you to review - the skipping should be reverted in DM-2536. But even that's pretty rare.

See the linked afw PR for a description of the changes. There are GitHub PRs already created for 7 packages: afw, meas_base, meas_algorithms, meas_astrom, meas_deblender, ip_diffim, and pipe_tasks. JIRA seems to be a bit slow at displaying them, but I think they'll turn up. I took some care to make sure these show the correct diffs; the branch the diff is relative to depends on whether there were changes on DM-2533 and/or DM-2534.

Everything looks very good to me. Overall it appears to be a nice improvement. I did add a few minor requests and comments to the pull requests.

Merged to master with tickets/DM-1766 (where changes after review were rebased).