RepeatAction fix

Fixed an error, which occured when the repeat counter formula is modified within its repeat block.

Consider the following When tapped script:
 * __Expected output:__ Execute 10 times and set object to Y-Position -90 (= 10 - 100)
 * __Current master-branch output:__ Execute 1 time and set object to Y-Position 0

![repeatActionTestProgram](https://f.cloud.github.com/assets/1931620/371598/d87e0da4-a33d-11e2-9d6d-ca5b784ddd4c.png)