images_register occasionally falls out of sync, yielding unhelpful errors

[liamegan]

Occasionally (and in a way that I haven't been able to find a repeatable test-case for), the images_register.json falls out of sync. When this happens it yields errors like:

./src/components/common/img/img.jsx
6:22 Error: Unable to resolve path to module '../../../../images_register.json'. import/no-unresolved

Which is unhelpful. It would be better if we could detect the missing module and provide a suggestion to fix it.

[andrewrubin]

Is this still an issue, I wonder, now that we've moved the Masher into its own package?