[Feature] Log X-Cld-Error header in dev mode

[colbyfayock]

Feature Request

Is your feature request related to a problem? Please describe.

Cloudinary returns an X-Cld-Error header on image error that typically includes something descriptive of the reason the error is failing.

To help debugging, we can log this error in to the console, but only on dev mode.

This would need to happen from within the onError handling where we currently poll for the image for handling images that are processing.