Blinking<A, B, BLINK_MILLIS, BLINK_PROMILLE>
BlinkingX<A, B, BLINK_MILLIS_FUNC, BLINK_PROMILLE_FUNC>
BlinkingL<B, BLINK_MILLIS_FUNC, BLINK_PROMILLE_FUNC>
Switches between A and B. A full cycle from A to B and back again takes BLINK_MILLIS milliseconds. If BLINK_PROMILLE is 500, we select A for the first half and B for the second half. If BLINK_PROMILLE is smaller, we get less A and more B. If BLINK_PROMILLE is 0, we get all B. If BLINK_PROMILLE is 1000 we get all A.