Print image sizes at build time

[lbussell]

Because we moved our ACR(s) to a more secure tenant, it is more difficult to inspect images in our ACR, even just for testing purposes images. One thing that is more difficult is seeing the size of images in the ACR.

To make troubleshooting easier, I propose that we print the disk and compressed size of each image we build, at build time (and potentially the size of the layers).