Add all the A tasks

Task/Active-object/JavaScript/active-object-1.js

@@ -0,0 +1,26 @@
+function Integrator(sampleIntervalMS) {
+    var inputF = function () { return 0.0 };
+    var sum = 0.0;
+
+    var t1 = new Date().getTime();
+    var input1 = inputF(t1 / 1000);
+
+    function update() {
+        var t2 = new Date().getTime();
+        var input2 = inputF(t2 / 1000);
+        var dt = (t2 - t1) / 1000;
+
+        sum += (input1 + input2) * dt / 2;
+
+        t1 = t2;
+        input1 = input2;
+    }
+
+    var updater = setInterval(update, sampleIntervalMS);
+
+    return ({
+        input: function (newF) { inputF = newF },
+        output: function () { return sum },
+        shutdown: function () { clearInterval(updater) },
+    });
+}