tests: Fixed a logging test.

* Test was failing due to misconfiguration; corrected this.

Signed-off-by: Joe MacMahon <joe.macmahon@cern.ch>
tests: Wrote a new schema test

* New test for converting the schema into a mapping.
* Minor code clarification in another schema test.

Signed-off-by: Joe MacMahon <joe.macmahon@cern.ch>