S3 Copy/Move performance optimizations

[araddon]

There are Copy/Move that are not currently implemented on S3. These are performance optimizations that when copy/move from s3 -> to s3 don't do network transfer, instead allow s3 to do the copy/move through native s3 api.

cloudstorage/store.go

Lines 73 to 85 in 2731960

	// StoreCopy Optional interface to fast path copy. Many of the cloud providers
	// don't actually copy bytes. Rather they allow a "pointer" that is a fast copy.
	StoreCopy interface {
	// Copy from object, to object
	Copy(ctx context.Context, src, dst Object) error
	}
	// StoreMove Optional interface to fast path move. Many of the cloud providers
	// don't actually copy bytes.
	StoreMove interface {
	// Move from object location, to object location.
	Move(ctx context.Context, src, dst Object) error
	}

Google implementation

cloudstorage/google/store.go

Line 174 in 2731960

// Copy from src to destination

[araddon]

Not entirely sure this can be pushed down, the copy partially can:
https://stackoverflow.com/questions/47334556/aws-sdk-go-s3-move-directory-between-bucket
https://stackoverflow.com/questions/28830839/aws-s3-move-an-object-to-a-different-folder