kibitzer whith engine like ProDeo

[lucabunns]

hello inspired from https://github.com/lukasmonk/lucaschess/issues/38

Some engines like ProDeo really prefer to be closed in a proper way sending quit instead of just killing the process.

there is the same problem engine don't close when instance launch from kibitzer

y can use lucas with externe engine like Prodeo every Prodeo version comes with wb2uci.eng file in this file for use with lucaschess TerminateHard = true default is false and no issue when close engine but if you launch a kibitzer whith Prodeo engine engine don't close when instance launch from kibitzer

and if you launch an another Prodeo kibitzer for each kibitzer there is an Prodeo kibitzer instance no killed When you quit lucachess the different Prodeo kibitzer instance will continue

[lukasmonk]

I have added to write quit when finnished. I hope this is enough.