Do not hardcode unit position in testing

Signed-off-by: Michal Čihař <michal@cihar.com>
Proper handling of bilingual json files (issue #488)

Signed-off-by: Michal Čihař <michal@cihar.com>
Add tests for JSON file format (issue #488)

Signed-off-by: Michal Čihař <michal@cihar.com>