Added info on the 'seq' argument to readme.txt.

webcrab/res/readme.txt

@@ -8,6 +8,7 @@ Mouse messages are:
   move - continue a trackpad movement
   end - end a trackpad movement
 All of the above take 2 arguments: x and y.
+Each touch has a "seq" argument that starts at 0 and increments with each move, to avoid out-of-order movements.
 Mouse movement is relative so don't worry about the absolute values.
 X is positive left, and Y is positive down.