[Kst] "Delay" plugin

[Brisset, Nicolas]

> Sounds useful...  
> -It should be implemented as a 'filter'.
OK, it's just a matter of adding one line in the .xml, right ?

> -It would be great if it could shift both forwards and backwards
Sure, I will do that: positive delay values => shift forwards, negative
delays => shift backwards. The only issue it raises is the name: "delay"
sounds like it can only delay. Maybe I should call it "shift", then ? Is
is clear enough for the end user ?

Nicolas