Mono doesnt work well with RootFolder of DesktopDirectory,
you end up being stuck in ~/Desktop/. Instead when being
run under mono use MyComputer, which dumps you to /
Mono will crash if you do a Rows.Clear() and the first row isnt visible. To
work around this, when running under mono force scroll to [0,0] cell before
issuing the Clear().
https://bugzilla.xamarin.com/show_bug.cgi?id=24372
Renamed Settings.MonoFileIO to Settings.IsUnix
Created Settings.IsMono
