Removed unused (test?) script.
Variable KEYS_TEST is undefined.

Don't remove files based on it.
Removed the experimental changes.

No longer necessary.
Made controller tests a smidge easier to read.
Reverted controller changes.

Reverted changeset fbb93717155f0cfc9482212bfd12f66169736ada from
src/connectors/cli/controller.py. The cli controller will start again.
Pants's cleanups: split connector creation, container tests.

1. Split class addressing and connector creation from same try block.

   It seemed reasonable as I wanted connector creation exceptions to
   bubble up, but that's just a mean-spirited approach.  Now, log
   errors when connectors fail.

2. Use the *in* operator instead of just *try*ing for containment.

   The tries were no-op and vulnerable to __contains__ overrides.
   This way, we explicitly execute exactly the ideas we mean.