Allow load from file with just action list
Split action, action_printer out of main script
Helpers for creating test inputs
Test runner and inputs for all actions
Tweak unknown and commentCard output.

- More defensive, name or url may not exist
- Remove extra newlines at end of message
Expected output for all actions
Rename test update actions for clarity
A couple minor id sanitations
Make string unicode handling consistent.

Fixes #3
Fix handling of attachments with no url field.

Make unknown no-url consistent (i.e. empty) as well, so no link is
generated.

Fixes #4