visor and backpack: add Off() synonym for API consistency

Signed-off-by: Ron Evans <[email protected]>

Author: deadprogram

backpack.go

@@ -31,6 +31,11 @@ func (b *BackpackDevice) Show() {
 	b.WriteColors(b.LED)
 }
 
+// Off turns off all the LEDs.
+func (b *BackpackDevice) Off() {
+	b.Clear()
+}
+
 // Clear clears the Backpack LEDs.
 func (b *BackpackDevice) Clear() {
 	b.SetColor(color.RGBA{R: 0x00, G: 0x00, B: 0x00})

examples/blink-all/main.go

@@ -21,8 +21,8 @@ func main() {
 			time.Sleep(500 * time.Millisecond)
 
 			antenna.Off()
-			visor.Clear()
-			backpack.Clear()
+			visor.Off()
+			backpack.Off()
 			time.Sleep(500 * time.Millisecond)
 		}
 	}

visor.go

@@ -33,6 +33,11 @@ func (v *VisorDevice) Show() {
 	v.WriteColors(v.LED)
 }
 
+// Off turns off all the LEDs.
+func (v *VisorDevice) Off() {
+	v.Clear()
+}
+
 // Clear clears the visor.
 func (v *VisorDevice) Clear() {
 	for i := range v.LED {