603f0e9 Add __init__.py for subjects submodule

Authored and Committed by Lukas Holecek 4 years ago
    Add __init__.py for subjects submodule
    
    This could possibly fix the fedora messaging having an issue with
    loading the submodule (#540).
    
    JIRA: FACTORY-5879
    
    Signed-off-by: Lukas Holecek <hluk@email.cz>