Pip, conda-pack, and Docker

This version improves support for pip packages with the add-packages, remove-packages, list-packages, and lock commands.

Secondly, two new options for exporting projects.

• anaconda-project archive --pack-envs <archive> will use conda-pack to include full Conda environments in the archive
• anaconda-project dockerize will use s2i-anaconda-project to build Docker images from your project

See the documentation for more details on how to use these new features.