Export current document as SVG when pressing Ctrl+Shift+S (#160)

* Export current document when pressing Ctrl+Shift+S

* Use a blob for download

* Add Ctrl + E shortcut, match on lower case

* Don't mount element in DOM

* Polish some keybindings

* Add initialization for MappingEntries

* Implement svg coloring

* Add newline after svg tag

* Add spaces to svg style format

* Fix more svg formatting

* Add space before />

* Remove duplicate whitespace

core/document/src/layers/rect.rs

@@ -22,7 +22,7 @@ impl LayerData for Rect {
 	fn render(&mut self, svg: &mut String) {
 		let _ = write!(
 			svg,
-			r#"<rect x="{}" y="{}" width="{}" height="{}" {} />"#,
+			r#"<rect x="{}" y="{}" width="{}" height="{}"{} />"#,
 			self.shape.min_x(),
 			self.shape.min_y(),
 			self.shape.width(),