crop effect

hi,

In some situations (like TV recordings) there are some scanlines (teletext, caption channels) that has to be hidden when doing a PIP, for example.
So a way to crop this lines would be needed, but I would prefer to have this in a separate crop effect, which offer more flexibility.
Maybe later we can combine several effects to a effect group that can be saved and recalled ...

I would like to vote for this effect. Its one of the effects I would depend on