[Paraview] Force or deactivate some Readers. Reuse the Paraview already running

[Utkarsh Ayachit]

> 1) I always work with xmdf files and every time I have to choose the reader
> to use in the menu, can we deactivate or force the use of a specific reader
> in the command line?

Not currently, but that's a nice and easy feature to add. Feel free to
report a feature request.

> 2) also if I run a second command line to run paraview (with a filename as
> argument) can we reuse the instance of paraview already running. (to compare
> results for example)

Not currently supported also, I am afraid.