better code formatting for blocks (xelatihy#145)

small fix to remove warnings

Return objects rather than pointers when possible.

Merge development branch with major refactoring throughout.

Yocto/GL Release 0.3.0

Major release with significantly simpler APIs.

- Math
    - templated math
    - transform code cleanup
- Shape
    - simpler and more explicit API for all tasks
- BVH
    - bvh works without sharing memory for better flexibility
    - support for arbitrary shape instancing
    - simpler API
    - more work still is needed for further cleanups that won't change the API
- Scene
    - support for multiple shapes per object
    - support for optional node hierarchy
    - support for optional animation hierarchy
- Procedural scene
    - define a procedural scene for simple examples
    - test generation uses the procedural scene
- Path trace
    - explicit management of pixel state
    - simpler API and internal implementation
    - more work still is needed for further cleanups that won't change the API
- OpenGL
    - explicit objects with state mirrored on the client
    - simpler API via objects, instead of untyped handles
- Internal
    - visitor API for enums and types
    - butter documentation extraction and formatting
- Apps
    - use reflection for command line and widgets
    - typed selection and update lists
    - procedural scene creation integration