//! This module contains the annotation system, that is in charge of administrating the [way points](waypoint_system),
//! the [paths](path_system) and the [regions](region_system).
//!
//! The app stays the single source of truth for what it hands in: positions, shapes,
//! symbols, colors, descriptions and flags are not handed back. The systems only
//! answer what they compute themselves, like the center of a region or the closest
//! point on a path.
pub