Builds on 331 to add tests

[simonwheatley]

Includes @richaber's fixes from #331, and includes some search tests and additional infrastructure to support these tests.

• [x] Fix fatals in tests (see #333)
• [x] Add basic tests for search
• [x] Add tests for search in the context of a static front page

[simonwheatley]

Looks like tests are failing for multisite, e.g. https://travis-ci.org/Automattic/babble/jobs/80895773 :grimacing:

[simonwheatley]

Looks like tests are failing for multisite, e.g. https://travis-ci.org/Automattic/babble/jobs/80895773 :grimacing:

Tests do pass when I manually run the series of actions in a real multisite, so something is affecting them in the PHPUnit environment.

[simonwheatley]

Restarting a Travis job due to a sudden database failure in mid-Behat testing… seems like this happens a fair amount currently. :unamused:

[david-binda]

Merged, thank you @richaber