Install Python software globally (not in user space)

[bittner]

Python software, such as youtube-dl, is currently installed as pip install --user, which entails some complications. In the idea of having software (installed with this Ansible role) updated automatically, that software should be installed globally on the system.

[bittner]

• Fixed for youtube-dl via 541c216#diff-e7ca546dadcb8b54e9ab41d5d076e30a.
• Needs decision for installing Pipenv.

Similar issues:

• Pyenv might be difficult to install globally as it's basically a user-space clone of a Git repository. All installed Pythons are created in that tree.
• Needs investigation whether Pythons can be created outside the repository location (e.g. when we're cloning the repo in /opt/pyenv/).
• Also, the pyenv configuration should be created globally or by something like the userdefaults script.