Remove the need for every module to define a widget.ShowHelp keyboard control

This common functionality is moved up to KeyboardWidget. Modules now
include widget.InitializeCommonControls() instead.

view/keyboard_widget.go

@@ -31,7 +31,7 @@ type KeyboardWidget struct {
 
 // NewKeyboardWidget creates and returns a new instance of KeyboardWidget
 func NewKeyboardWidget(app *tview.Application, pages *tview.Pages, settings *cfg.Common) KeyboardWidget {
-	return KeyboardWidget{
+	keyWidget := KeyboardWidget{
 		app:      app,
 		pages:    pages,
 		settings: settings,
@@ -40,6 +40,8 @@ func NewKeyboardWidget(app *tview.Application, pages *tview.Pages, settings *cfg
 		charHelp: []helpItem{},
 		keyHelp:  []helpItem{},
 	}
+
+	return keyWidget
 }
 
 // SetKeyboardChar sets a character/function combination that responds to key presses
@@ -70,6 +72,12 @@ func (widget *KeyboardWidget) SetKeyboardKey(key tcell.Key, fn func(), helpText
 	}
 }
 
+// InitializeCommonControls sets up the keyboard controls that are common to
+// all widgets that accept keyboard input
+func (widget *KeyboardWidget) InitializeCommonControls() {
+	widget.SetKeyboardChar("/", widget.ShowHelp, "Show/hide this help prompt")
+}
+
 // InputCapture is the function passed to tview's SetInputCapture() function
 // This is done during the main widget's creation process using the following code:
 //