Calling `'That's all at handstroke'`

[centreboard]

'That's all at handstroke' becomes Change method in the RR audio

1) Update RR to use That's all audio
2) Edit the call to just emit That's all when processed by ComplibCompositionGenerator

[kneasle]

I like option two more - this is a side effect of using an API designed for Handbell Stadium, and hopefully people will notice the super early That's All and stop at handstroke anyway. That reminds me actually, we should probably stop Wheatley from leaving the bells up at handstroke if --stop-at-rounds is set... Snap I had not seen your PR...