Preserve Image Metadata

[awalter17]

When an input image is used to generate an output image, the output image does not maintain the metadata of its "source"/"parent" image. This is an issue.

That being said, we don't want to preserve all the metadata. There needs to be some selectivity in which metadata is attached.

Ideally we'd just want to preserve a reference to the "source"/"parent" image, which would of course still have its metadata. And from there the user can decide which metadata to propagate to the "child" image.