Analytics: fixing weight computation in Smoothing plugin

analytics/operators/smoothing/SmoothingSensorBase.h

@@ -77,6 +77,11 @@ public:
     
     void smoothAndStore(reading_t r) {
         double weight = (double)(r.timestamp - _currTs) / (double)_range;
+        if (weight > 1.0) {
+            weight = 1.0;
+        } else if (weight < 0.0) {
+            weight = 0.0;
+        }
         _currValue = _last ? (_currValue * (1.0 - weight) + (double)r.value * weight) : (double)r.value;
         _currTs = r.timestamp;
         if(r.timestamp - _last > _range) {