Support for containerized environments

New Features

• Run docker-slim in containers.
• New distribution option (dslim/docker-slim image available in Docker Hub).
• Archive docker-slim state into a separate Docker volume.

Improvements

• Default to continuing docker-slim execution after the http probing step is done when http probing is enabled.
• Improved IPC.
• Improved seccomp and metadata artifact copy option.
• Improved execution report.