Change icon sorting in grid.

Sort icons in grid by shape identifiers instead of tag priority.

roentgen/grid.py

@@ -91,13 +91,13 @@ def draw_all_icons(
         ", ".join(sorted(extractor.shapes.keys() - specified_ids)) + "."
     )
 
-    for icon in icons:  # type: Icon
+    for icon in icons:
         icon.draw_to_file(join(
             output_directory, f"{' + '.join(icon.get_names())}.svg"
         ))
 
     draw_grid(
-        output_file_name, icons, columns, step,
+        output_file_name, sorted(icons), columns, step,
         background_color=background_color
     )
 

roentgen/icon.py

@@ -362,7 +362,15 @@ class Icon:
         self.shape_specifications += specifications
 
     def __eq__(self, other) -> bool:
-        return sorted(self.shape_specifications) == sorted(other.shape_specifications)
+        return sorted(self.shape_specifications) == sorted(
+            other.shape_specifications
+        )
+
+    def __lt__(self, other) -> bool:
+        return (
+            sorted(self.shape_specifications)[0].shape.id_
+            < sorted(other.shape_specifications)[0].shape.id_
+        )
 
 
 @dataclass