zendesk/persistence — pull request #4 by samshull (2014-07-03 01:51:13+00:00)
Title: Handle callback always

Sometimes passing an undefined handler to redis causes a strange rearrangement
of arguments. This commit ensures that a callback is always passed that
is not null or undefined.

/cc @zendesk/zendesk-radar

### Steps to merge
- [ ] :+1: of the team

### Risks
- None