(stable) Continue on bad database configuration from select scripts
Summary: Ref T11589. Provide a way for scripts to say "just continue if database config fails", and use it in bin/config and bin/storage.
Test Plan:
- Broke database config.
- Ran bin/config, worked fine.
- Ran bin/storage, got helpful "set up the database" message.
- Ran bin/repository, got fatal.
- Ran normal site with valid/invalid config, got proper feedback.
Reviewers: chad
Reviewed By: chad
Maniphest Tasks: T11589
Differential Revision: https://secure.phabricator.com/D16502