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- Added an option to print out only apt and pip installable packages as commands.
- Added warning when neither the ``ROS_DISTRO`` environment variable is set nor the ``--rosdistro`` option is used.
- Fixed a bug related to group id resolution.
- Switched to using DNF instead of YUM for Fedora 22+.
- Fixed a bug where pip packages were not detected for older versions of ``pip``.
- Fixed a bug where dependencies of packages were gotten from the wrong ``package.xml`` when that package was being overlaid with local packages.