Add oriented bounding box and convex hull types

[alice-i-cecile]

/// A 2-dimensional oriented bounding box with coordinate type C
#[derive(Debug, Component, Clone, PartialEq)]
pub struct OrientedBoundingBox<C: Coordinate> {
    center: Position<C>,
    local_x: Direction,
    local_y: Direction,
    halfwidth_extent_x: C,
    halfwidth_extent_y: C,
}

/// A 2-dimensional convex hull with coordinate type C
#[derive(Debug, Component, Clone)]
pub struct ConvexHull<C: Coordinate> {
    /// The points which define a convex region
    pub hull_points: Vec<Position<C>>,
}