Add Concept directory back into Flame trunk development line:
    
        Content that can be generated automatically (e.g., Distro, Promo)
        are produced only when a new branch is created. Such content is
        not created in trunk.
    
        In trunk we maintain backgrounds, colors, concept, and
        screenshots. Once backgrounds are ready to produce distro and
        promotion stuff, we use centos-art.sh command line to create a
        branch with all information required to keep going with the theme
        production.
    
        At this point you may continue working on trunk's backgrounds and
        later merge changes up to the branch. Once changes have been
        merged you render theme information inside branches directory
        structure, which at this point contains all the information
        required to perform rendering tasks.
    
        Once branch is created, theme visual style is divided in two
        development lines. The trunk development line and the branch
        development line. As convenction, we create a branch development
        line from trunk, once the visual style on trunk is ready to be
        propagated to all visual manifiestations of CentOS corporate
        visual identity.
    
        Inside branches, we mainly perform rendering tasks and decide
        which design model does centos-art.sh script uses in order to
        propagate the visual style of backgrounds. If we need to improve
        branch visual style, we use backgrounds on branch development
        lines. Otherwise, if we want to improve visual style as a previous
        plan to create a new branch development line (i.e., with a
        ``refreshed'' the visual style).
    
        Once a branch is considered ready for production environments, we
        create a tag from it. Tags are immutable.