Update readme

Author: youjinp

README.md

@@ -90,6 +90,9 @@ struct ContentView: View {
 
  var body: some View {
  ZStack {
+ // This is just a dummy view to present the contact picker,
+ // it won't display anything, so place this anywhere.
+ // Here I have created a ZStack and placed it beneath the main view.
  ContactPicker(
  showPicker: $showPicker,
  onSelectContact: {c in