It's the Szmyd.Orchard.Module.Menu module.
I wish I knew what I possibly could have done to step on it so I could file a bug with the repro steps, but I'm not even sure what I did or if it was even me.
I deleted the module folder and was able to get in to command line. I ran my datamigration and then put the module folder back. The site seems to be running perfectly fine, including the Menu module. I'll post the stack trace and error as a bug and then
try to reinstall the Menu module to see if that resolves the issue.