TODO

Meta:
    - establish naming convention for State::Context event names, and switch        (short)

State:
    + work out Context object lifetimes                                             (medium)

GUI:
    + stateful GUI, i.e. registry, persistence, etc.                                (medium)
    - rearchitect to allow for multiple GUI items per Renderable                    (medium)
    - support [simple] font kerning                                                 (medium)
    - GUI styling support                                                           (medium)
    - font text wrapping and styling                                                (medium)
    - TextDisplay proper line spacing                                               (short)

Rendering:
    + skeleton-based animation support                                              (long)
        - how many bones per vertex should be supported?
    + support loading textures for models                                           (medium)
    + support assimp material system                                                (long)
    - load textures from model files, if present                                    (medium)
    - improve rendering timer support w/non-string based timers                     (short)
    - support custom shader types for models (overload specific material names?)    (short)
    - support conditional rendering                                                 (short)
        - needs occulsion queries                                                   (short)
    - transform feedback infrastructure for accelerated rendering etc.              (long)
    - uniform buffer object support                                                 (medium)
    - implement support for multi-pass rendering on the same rendering stage        (medium)
    - deterministic rendering order in RenderableContainer                          (medium)