Drop indices and migrate relationship columns

Added a helper to drop indicies because migrations were failing when trying to recreate indicies.
Noticed relationship data wasn't being copied over, so added it back in with a couple of tweaks we needed.
Merge pull request #129 from jasper-ch-chan/master

Null safeguards Issue #127
Merge pull request #128 from jcarroll3/master

Drop indices and migrate relationship columns