Add tasks for all the new languages

Task/Best-shuffle/Phix/best-shuffle.phix

@@ -0,0 +1,15 @@
+constant tests = {"abracadabra", "seesaw", "elk", "grrrrrr", "up", "a"}
+string s,t
+    for test=1 to length(tests) do
+        s = tests[test]
+        t = shuffle(s)
+        for i=1 to length(t) do
+            for j=1 to length(t) do
+                if i!=j and t[i]!=s[j] and t[j]!=s[i] then
+                    {t[i], t[j]} = {t[j], t[i]}
+                    exit
+                end if
+            end for
+        end for
+        printf(1,"%s -> %s (%d)\n",{s,t,sum(sq_eq(t,s))})
+    end for

Task/Best-shuffle/Sidef/best-shuffle.sidef

@@ -0,0 +1,22 @@
+func best_shuffle(String orig) -> (String, Number) {
+
+    var s = orig.chars
+    var t = s.shuffle
+
+    s.range.each { |i|
+        s.range.each { |j|
+            if (i!=j && t[i]!=s[j] && t[j]!=s[i]) {
+                t[i, j] = t[j, i];
+                break;
+            }
+        }
+    }
+
+    var word = t.join;
+    (word, orig ^ word -> count("\0"));
+}
+
+<abracadabra seesaw elk grrrrrr up a>.each { |word|
+    var (sword, score) = best_shuffle(word)
+    "%-12s %12s: %d\n".printf(word, sword, score)
+}