Add tasks for all the new languages

Task/Binary-search/Sidef/binary-search-1.sidef

@@ -0,0 +1,14 @@
+func binary_search(a, i) {
+
+    var l = 0;
+    var h = a.end;
+
+    while (l <= h) {
+        var mid = (h+l / 2 -> int);
+        a[mid] > i && (h = mid-1; next);
+        a[mid] < i && (l = mid+1; next);
+        return mid;
+    }
+
+    return -1;
+}

Task/Binary-search/Sidef/binary-search-2.sidef

@@ -0,0 +1,13 @@
+func binary_search(arr, value, low=0, high=arr.end) {
+    high < low && return -1;
+    var middle = (high+low / 2 -> int);
+
+    if (value < arr[middle]) {
+        return binary_search(arr, value, low, middle-1);
+    }
+    elsif (value > arr[middle]) {
+        return binary_search(arr, value, middle+1, high);
+    }
+
+    return middle;
+}

Task/Binary-search/Sidef/binary-search-3.sidef

@@ -0,0 +1 @@
+say binary_search([34, 42, 55, 778], 55);       #=> 2