The idea of splitting integration from unittests is good in theory
but leads to a lot of mental overhead. Besides whenever a tests
interacts with a database it isn't a unittest anyway.

Better to use filenames which are commonly used in the python word then
custom ones.

Add the tests/unit/search/__init__.py so that nose can discover the 
tests in this directory.

Simplify the API to allow easier testing, and simplify the
implementation.