Sync docs to get Stamps rotation info

docs/gl_ES.UTF-8/README.txt

@@ -309,9 +309,28 @@ Ferramentas dispoñíbeis
            previamente (como a imaxe dun cabalo, unha árbore ou a lúa) na súa
            imaxe.
 
-           Ao mover o rato arredor do lenzo, un contorno segue o rato,
-           amosando onde se colocará o selo e o grande que será. Prema para
-           colocar o selo.
+           As you move the mouse around the canvas, an outline follows the
+           mouse, showing where the stamp will be placed, and how big it will
+           be. Click on the canvas where you wish to place the stamp.
+
+                Normal Stamps Mode
+
+                        Now you can move the mouse around the canvas to
+                        rotate the stamp.
+
+                        Click the mouse button again and the stamp will be
+                        added to the drawing.
+
+                Simple Stamps Mode
+                        If "stamp rotation" option is disabled, the stamp
+                        will be drawn on the canvas when you let go of the
+                        mouse button. (There's no rotation step.)
+
+                        ⚙ See the "Options" documentation to learn about the
+                        "stamp rotation" ("stamprotation") option.
+
+           📜 Note: The stamp rotation feature was added to Tux Paint in
+           version 0.9.29.
 
            Pode haber numerosas categorías de selos (por exemplo, animais,
            plantas, espazo exterior, vehículos, persoas, etc.). Use as