Add tasks for all the new languages

Task/Nth/Sidef/nth.sidef

@@ -0,0 +1,8 @@
+func nth(n) {
+    static irregulars = Hash.new(<1 ˢᵗ 2 ⁿᵈ 3 ʳᵈ 11 ᵗʰ 12 ᵗʰ 13 ᵗʰ>...);
+    n.to_s + (irregulars{n % 100} \\ irregulars{n % 10} \\ 'ᵗʰ');
+}
+
+[range(0, 25), range(250, 265), range(1000, 1025)].each { |r|
+    say r.map {|n| nth(n) }.join(" ");
+}