[vtkusers] Memory usage and ReleaseDataFlag

[John Biddiscombe]

Part1)
If a filter outputs a dataset and
filter->SetReleaseDataFlag is true
and the output is used as an input to multiple filters. Should the data 
only be released when all filters consuming the output have updated. I seem 
to be getting multiple updates and trouble.

part 2)
An image filter outputting an image which is passed into vtkTexture can't 
have ReleaseDataFlag(1) can it? Otherwise the texture reexecutes on every 
render. True or false (true from where I'm sitting, but I don't really 
believe it). Have I done something wrong.

Thanks

JB