add size to inspect
add size to inspect

Signed-off-by: Zhang Kun <353d5dcc45e8dee680a183df3d3ab57bd598a8d0@gmail.com>

jwhonce/engine-api,msabansal/engine-api,docker/engine-api,vdemeester/engine-api,rhatdan/engine-api,mikedougherty/engine-api,thaJeztah/engine-api