### New `math` module
* Traits for error-tolerant floating-point comparisons
* Traits for interpolation and easing
* Bevy plugin to manage 3D interpolations with ECS components
### `skybox` module refactor
* ECS resource to enable external skybox selection/updates
* System run conditions for more idiomatic/ECS-friendly control flow
### Camera controller refactor
* Renamed from `orbit_cam` to `camera_controller`
* Now delegates to the new interpolation plugin for WASD motion smoothing
* Simple API for attaching the `CameraController` component to the camera from
another module -- this resolves an awkward separation-of-concerns situation
where we had to configure a bunch of render-quality settings in the camera
controller module
### Scene module refactor
* Renamed from `test_scene` to `scene`
* This module is now responsible for configuring the skybox
* This module is now responsible for spawning the camera and configuring the
render settings
Danny McGee