Removing and adding a new field with same name causes DB error

[kaidesu]

What is the issue?

If removing a field and adding a new one with the same name, an error is thrown. Specifically, it does not remove the old column and instead attempts to create a new one with the same name, resulting in a database error.

[thekanbo]

Resolved in https://github.com/fusioncms/fusioncms/pull/92/files