Added Tracking Screen and implemented "Reference Tracking" and "Color Region Selection"

common/app/screen_tracking.h

@@ -0,0 +1,37 @@
+#include "screen.h"
+
+/**
+ * @addtogroup screens
+ */
+/*@{*/
+
+/**
+ * @defgroup tracking Tracking (Screen)
+ * The Tracking-Screen shows the object-tracking and allows some configuration
+ */
+/*@{*/
+
+
+/**
+ * Enum which contains the available tracking implementations
+ */
+enum Tracking_Implementation {
+	OUR_TRACKING,     //!< Our own tracking PID implementation
+	REFERENCE_TRACKING//!< Pixy's internal tracking implementation
+};
+
+/**
+ * Sets the current Mode/Tracking Implementation. Call this before using the screen obtained by get_screen_tracking()
+ * @param impl The new mode
+ */
+void tracking_set_mode(enum Tracking_Implementation impl);
+
+/**
+ * Returns a pointer to the tracking screen
+ * \sa gui_screen_navigate
+ * @return
+ */
+SCREEN_STRUCT* get_screen_tracking();
+
+/*@}*/
+/*@}*/