The .salt directory should be owned by the ssh login user

Since the ssh login user is used to drop the deployment file they need
write permissions, and since the login user can sudo they have rights to
manage the salt runs. When salt runs as root it will still have access
to said files.
We still need more validation around the integrety of the passed files
Add untaring the thin tarball into the shim

Also add hooks in to checksum the thin tarball
Add function to generate the hash of the thin tarball
Add hooks to geenrate the thin sum and pass to the shim