Make automatic_rotate relative, allow setting rotation (#8468)

automatic_rotate does not make sense if it is absolute. Make it relative.

To avoid bouncing, set_rotation did not update the client when automatic_rotate was set. That's no longer necessary because the new spinning method applies the rotation on top of the current one, and the updates are necessary for set_rotation to actually transform the object.

Co-authored-by: ANAND <ClobberXD@gmail.com>

Co-authored-by: Pedro Gimeno <pgimeno@users.noreply.notabug.org>

doc/lua_api.txt

@@ -6555,6 +6555,7 @@ Player properties need to be saved manually.
 
         automatic_rotate = 0,
         -- Set constant rotation in radians per second, positive or negative.
+        -- Object rotates along the local Y-axis, and works with set_rotation.
         -- Set to 0 to disable constant rotation.
 
         stepheight = 0,