add optional diagnostics around fsharpi exit
add optional diagnostics around fsharpi exit

nosami/xamarin-monodevelop-fsharp-addin,Ming-Tang/fsharpbinding,Ming-Tang/fsharpbinding,fsharp/fsharpbinding,xamarin/fsharpbinding,fsharp/xamarin-monodevelop-fsharp-addin,Ming-Tang/fsharpbinding,xamarin/fsharpbinding,fsharp/fsharpbinding,fsharp/xamarin-monodevelop-fsharp-addin,nosami/xamarin-monodevelop-fsharp-addin,fsharp/fsharpbinding