fix couple of problems in the smooth

sensors.py

@@ -33,8 +33,8 @@ WINDOW_SIZE_S = 5
 
 class Sensor():
     def __init__(self, autocorr=0.7):
-        # We won't sample at more than 10Hz, so this is safe
-        self.history = deque([], int(WINDOW_SIZE_S * 10))
+        # FIXME: DEPENDS ON SAMPLING RATE
+        self.history = deque([], int(WINDOW_SIZE_S * 2))
         
         ## This is just for debugging
         self.prevval = random() * 100
@@ -72,8 +72,13 @@ class GPIOState(Sensor):
             print(f"Could not read pin {self.pin}")
             self.value = 0
         self.time = perf_counter()
-        
-        return self.store(self.time, self.transform(self.value))
+
+        # Even if we don't need to return the smoothed value, we still smooth it
+        # to get the percentage of use over the period (if it will be needed)
+        value = self.transform(self.value)
+        self.store(self.time, value)
+
+        return (self.time, value)
 
 class Temperature1W(Sensor):
     def __init__(self, address):