Massively reorganize and clean up the whole Rust codebase (#478)

* Massively reorganize and clean up the whole Rust codebase

* Additional changes during code review

editor/src/viewport_tools/tool_message.rs

@@ -0,0 +1,44 @@
+use super::tool::ToolType;
+use super::tool_options::ToolOptions;
+use crate::message_prelude::*;
+
+use graphene::color::Color;
+
+use serde::{Deserialize, Serialize};
+
+#[remain::sorted]
+#[impl_message(Message, Tool)]
+#[derive(PartialEq, Clone, Debug, Serialize, Deserialize)]
+pub enum ToolMessage {
+	ActivateTool(ToolType),
+	#[child]
+	Crop(CropMessage),
+	DocumentIsDirty,
+	#[child]
+	Ellipse(EllipseMessage),
+	#[child]
+	Eyedropper(EyedropperMessage),
+	#[child]
+	Fill(FillMessage),
+	#[child]
+	Line(LineMessage),
+	#[child]
+	Navigate(NavigateMessage),
+	NoOp,
+	#[child]
+	Path(PathMessage),
+	#[child]
+	Pen(PenMessage),
+	#[child]
+	Rectangle(RectangleMessage),
+	ResetColors,
+	#[child]
+	Select(SelectMessage),
+	SelectPrimaryColor(Color),
+	SelectSecondaryColor(Color),
+	SetToolOptions(ToolType, ToolOptions),
+	#[child]
+	Shape(ShapeMessage),
+	SwapColors,
+	UpdateHints,
+}