add front flip and back flip capabilities to step 6

drone/minidrone/README.md

@@ -98,6 +98,8 @@ Now it is time for free flight, controlled by you, the human pilot. Plug in the
 * X           - Land
 * Left stick  - altitude
 * Right stick - direction
+* L1          - Front flip
+* R1          - Back flip
 
 
 IMPORTANT NOTE: you must press the "P3" button when your program first runs for the "clone" DS3 joysticks we are using to fully turn on.

drone/minidrone/step6/joystick.go

@@ -72,6 +72,14 @@ func startJoystick() {
 		rightY.Store(val)
 	})
 
+	stick.On(joystick.L1Press, func(_ interface{}) {
+		drone.FrontFlip()
+	})
+
+	stick.On(joystick.R1Press, func(_ interface{}) {
+		drone.BackFlip()
+	})
+
 	go handleLeftJoystick()
 	go handleRightJoystick()
 }