Added effect marquee, which will scroll a given message through the display.

include/effect_marquee.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "prototypes.h"
+#include "functions.h"
+#include "Effect.h"
+
+class MarqueeEffect : public Effect {
+private:
+	Window* window = new Window(0, 0, LED_WIDTH, LED_HEIGHT-6);
+	String _text = String("No text set +++ ");
+	saccum78 _position = (window->width<<8);
+public:
+    boolean supports_window = true;
+    boolean can_be_shown_with_clock();
+    void loop();
+    void apply_option(String key, String value) override;
+};
+