Implemenation of Optional attributes

commit 710dab82e5d596b6147f9b57c9818b8cf6de49e0
Author: Paweł Dolega <pdolega@nexelem.com>
Date:   Thu Nov 20 06:55:06 2014 +0100

    Actual value generation

commit ca37836d9a06491944c65052ebf6e0a9eddaea99
Author: Paweł Dolega <pdolega@nexelem.com>
Date:   Thu Nov 20 06:39:31 2014 +0100

    Simple option handling implementation

commit fa0b031cd2c74be245f3ec1ac81266f6d6fbca06
Author: Paweł Dolega <pdolega@nexelem.com>
Date:   Wed Nov 19 11:35:38 2014 +0100

    Handling Options