Singularity 2.4.4 Release

Hello Singularity users

This is a bug fix point release to the 2.4 feature branch. It removes the docker-extract functionality that was added in version 2.4.3. This feature added a new dependency and was subsequently found to increase the Singularity attack surface by unnecessarily linking the action-suid binary to libarchive, when compiled on specific Linux distributions. This feature will be re-implemented in a future release.

As always, please report any bugs to:
https://github.com/singularityware/singularity/issues/new