Enable searching messages by status again, refs D101, refs T189

Test Plan:
```
bin/behat -c application/tests/behat.yml -f progress application/tests/features/api.messages.feature
```

Reviewers: rjmackay

Reviewed By: rjmackay

Subscribers: eyedol, dkobia

Maniphest Tasks: T189

Differential Revision: https://phabricator.ushahidi.com/D103