Pager response design for containers and blobs should be improved

[kimprice]

This issue came up from the November Blob Storage UX study in a post discussion with @JeffreyRichter

 // EXAMPLE: List containers in a storage account
    for pager := service.ListContainers(nil); pager.NextPage(ctx); {
        // BUG: This design should be improved
        for _, con := range pager.PageResponse().ListContainersSegmentResponse.ContainerItems {
            fmt.Println(con.Name)
        }
    }

    // EXAMPLE: List blobs in a container
    for pager := container.ListBlobsFlat(nil); pager.NextPage(ctx); {
        // BUG: This design should be improved
        for _, b := range pager.PageResponse().ListBlobsFlatSegmentResponse.Segment.BlobItems {
            fmt.Println(b.Name)
        }
    }

[jhendrixMSFT]

We've updated azblob to use the new pattern for pagers. This is in v0.5.0.

pager := containerClient.NewListBlobsFlatPager(nil)

nameMap := testcommon.BlobListToMap(blobNames)

for pager.More() {
	resp, err := pager.NextPage(context.Background())
	// TODO: handle error

	for _, blob := range resp.Segment.BlobItems {
		// do something with blob
	}
}