trim blueprints before saving

src/editor.rs

@@ -277,6 +277,7 @@ impl Editor {
 				}
 			}
 		}
+		board.trim_size(0);
 		let mut blueprint = Blueprint::new(&board, self.blueprints.len());
 		if !self.new_blueprint_name.is_empty() {
 			blueprint.name = self.new_blueprint_name.clone();