Move externals to a contrib folder
Fix CLI that fails for bootstrap
Don't configure externals in the site

Use plugins for this!
Ignore eggs in git
Refactor context tests
Add "builtin plugins" and use them for context
Remove variables from CLI invocation

Use plugins and / or config!
Use inspect to determine how to call plugins

This might fail sometimes when the other method (try and cath TypeError)
would work, but does not silently not run a plugin anymore.