Add tasks for all the new languages

Task/Odd-word-problem/Sidef/odd-word-problem.sidef

@@ -0,0 +1,24 @@
+func rev {
+    (var c = STDIN.getc) \\ return()
+    if (c ~~ /^[a-z]\z/i) {
+        var r = rev()
+        print c
+        return r
+    }
+    return c
+}
+
+var (n=0, l=false)
+while (defined(var c = STDIN.getc)) {
+    var w = (c ~~ /^[a-z]\z/i)
+    ++n if (w && !l)
+    l = w
+    if (n & 1) {
+        print c
+    } else {
+        var r = rev()
+        print(c, r)
+        n = 0
+        l = false
+    }
+}