Ready for review:

• I've forked LSST/DMS/meas_multifit.git to contrib/meas_modelfit.git, and (on branch u/jbosch/DM-1284) done a lot of regexp replacement to change the names of files, directories and namespaces. There are no other changes, so I don't actually think it's necessary to inspect these manually in detail.
• I've added meas_modelfit to lsst_apps' dependencies on u/jbosch/DM-1284 of lsst_apps.

After the review, I'll need help with the next two steps:

• A gitolite admin will need to move the package from contrib to LSST/DMS, and delete meas_multifit from LSST/DMS to avoid future confusion.
• A GitHub admin will need to rename the meas_multifit mirror there to modelfit.

After that, I'll merge the u/jbosch/DM-1284 branches to master and close the issue.

Should MeasureMultiTask and its config value usePreviousMultiFit be changed? Or is the comment that it has bitrotted in overview.dox sufficient? I presume that MultiModel is still an appropriate name.

Looks fine otherwise. Let me know when you're ready for the gitolite moves.

Should MeasureMultiTask and its config value usePreviousMultiFit be changed?

This and MeasureMulti are some of the few names in the package that actually do refer to the multifit procedure, so they should remain as they are.

Please go ahead with the gitolite moves whenever convenient.

gitolite moves are done. I am hoping that the mirroring will take care of GitHub and will fix manually if not.

You were right; I needed to rename on GitHub to keep the comments/PRs. I removed the mirror and renamed the repo. But I'm not sure the mirroring is working properly; I don't see u/jbosch/DM-1284... I'm wondering if the fork+rename on the gitolite side is messing with something.

Got it to mirror properly with some manual help; I think it would have caught up eventually but maybe not until the next modification to meas_modelfit.

Thanks for the help! Everything is now merged.