Errors while saving `created_at`

[Ryan Neal]

- Do you want to request a feature or report a bug?
bug

- What is the current behavior?
This is getting logged after some saves. Not sure where nor why

(/go/src/github.com/netlify/gocommerce/api/order.go:401)
[2017-11-18 00:51:42]  Error 1292: Incorrect datetime value: '0000-00-00' for column 'created_at' at row 1

(/go/src/github.com/netlify/gocommerce/api/order.go:401)
[2017-11-18 00:51:42]  Error 1292: Incorrect datetime value: '0000-00-00' for column 'created_at' at row 1

(/go/src/github.com/netlify/gocommerce/api/order.go:401)
[2017-11-18 00:51:42]  Error 1292: Incorrect datetime value: '0000-00-00' for column 'created_at' at row 1

- If the current behavior is a bug, please provide the steps to reproduce.

- What is the expected behavior?
Not have an error

- Please mention your Go version, and operating system version.
go1.8

[Bret Comnes]

@mraerino You marked this as ✅in the contract, did this get addressed? Asking because this issue is still open.

[Bret Comnes]

Decided this was low priority in the current refresh sprint.