edit: pass event.Ch to OnKeyPress callback

It seems beneficial the callback to also know the event.Ch so we can
implement more "sophisticated" field filling validation strategies.

demos/maindemo/clui_demo.go

@@ -91,7 +91,7 @@ func createView() {
 
 	ui.ActivateControl(view, edit)
 
-	edit.OnKeyPress(func(key term.Key) bool {
+	edit.OnKeyPress(func(key term.Key, ch rune) bool {
 		if key == term.KeyCtrlM {
 			v := edit.Title()
 			logBox.AddItem(fmt.Sprintf("New PB value(KeyPress): %v", v))

edit.go

@@ -15,7 +15,7 @@ func (e *EditField) OnChange(fn func(Event)) {
 // the controls is active. If a handler processes the key it should return
 // true. If handler returns false it means that the default handler will
 // process the key
-func (e *EditField) OnKeyPress(fn func(term.Key) bool) {
+func (e *EditField) OnKeyPress(fn func(term.Key, rune) bool) {
 	e.onKeyPress = fn
 }
 

edit_osx.go

@@ -30,7 +30,7 @@ type EditField struct {
 	showStars bool
 
 	onChange   func(Event)
-	onKeyPress func(term.Key) bool
+	onKeyPress func(term.Key, rune) bool
 
 	lastEvent time.Time
 }
@@ -93,7 +93,7 @@ func (e *EditField) ProcessEvent(event Event) bool {
 
 	if event.Type == EventKey && event.Key != term.KeyTab {
 		if e.onKeyPress != nil {
-			res := e.onKeyPress(event.Key)
+			res := e.onKeyPress(event.Key, event.Ch)
 			if res {
 				return true
 			}

edit_other.go

@@ -28,7 +28,7 @@ type EditField struct {
 	showStars bool
 
 	onChange   func(Event)
-	onKeyPress func(term.Key) bool
+	onKeyPress func(term.Key, rune) bool
 }
 
 // NewEditField creates a new EditField control
@@ -84,7 +84,7 @@ func (e *EditField) ProcessEvent(event Event) bool {
 
 	if event.Type == EventKey && event.Key != term.KeyTab {
 		if e.onKeyPress != nil {
-			res := e.onKeyPress(event.Key)
+			res := e.onKeyPress(event.Key, event.Ch)
 			if res {
 				return true
 			}