Added effect "snake".

include/config.sample.h

@@ -53,6 +53,9 @@
 
 #define EFFECT_CONFETTI_PIXELS_PER_LOOP 2
 
+#define EFFECT_SNAKE_DIRECTION_CHANGE 10
+#define EFFECT_SNAKE_SLOWDOWN 2
+
 #ifdef DEBUG
   #define LOG(x) Serial.print(x);
   #define LOGln(x) Serial.println(x);