Migrations: Detect renamed properties

[bricelam]

We currently detect renaming a column, but detecting renamed properties is harder because they could easily be intended for adding and removing a column.

We could go down the path of using contextual information like #5155 & #6404 propose, but that seems a little excessive. We could also mimic EF6 where if 80% of the metadata is the same, we consider it a rename, but this yielded false positives.

I propose we consider a column renamed if only the name is different. This will catch the same cases as the two referenced issues, and hopefully yield less false positives.