Add tasks for all the new languages

Task/Accumulator-factory/Sidef/accumulator-factory-1.sidef

@@ -0,0 +1,10 @@
+class Accumulator(sum) {
+    method add(num) {
+        sum += num;
+    }
+}
+
+var x = Accumulator(1);
+x.add(5);
+Accumulator(3);
+say x.add(2.3);               # prints: 8.3

Task/Accumulator-factory/Sidef/accumulator-factory-2.sidef

@@ -0,0 +1,8 @@
+func Accumulator(sum) {
+    func(num) { sum += num };
+}
+
+var x = Accumulator(1);
+x(5);
+Accumulator(3);
+say x(2.3);                  # prints: 8.3