[tests] use real amazon libs in tests.
Merge branch 'use-real-amazon-libs-in-dev-envs' into resolver-do-not-expose-target-path
use path and image vars names instead of originalXXX
[resolver] use path to remove cached images.
[amazon resolver] use objectPath instead of targetPath.
fix doc block of resolver interface method.
Filesystem not a string
do not use targetPath that much.