release v1.5

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

Merge pull request containers#586 from mtrmac/mpg-fixes

Fix progress bar cleanup, and other small cleanups

Merge pull request containers#545 from vrothberg/parapull

parallel copying

Merge pull request containers#536 from mtrmac/blob-info-caching

Blob info caching + mount/reuse

Merge pull request containers#536 from mtrmac/blob-info-caching

Blob info caching + mount/reuse