more and better samples for Nu, Racket, Scala

- 99 bottles of beer is more substantial than hello world
 - also fixed chmod 755 on several .script! files

samples/Scala/99-bottles-of-beer.script!

@@ -0,0 +1,40 @@
+#!/bin/sh
+exec scala "$0" "$@"
+!#
+
+object Beers extends Application {
+
+	def bottles(qty : Int, f : => String) = // higher-order functions
+		qty match {
+			case 0 => "no more bottles of beer" + f
+			case 1 => "1 bottle of beer" + f
+			case x => x + " bottles of beer" + f
+		}
+
+	def beers(qty : Int) = bottles(qty, " on the wall.")
+
+	def sing(qty : Int)(implicit song : String) : String = {
+		def takeOne =
+			qty match {
+				case 0 => "Go to the store and buy some more."
+				case x => "Take one down and pass it around."
+			}
+
+		def nextQty = // nested functions
+			if (qty == 0) 99
+			else qty - 1
+
+		def refrain = {
+			beers(qty).capitalize + " " + bottles(qty, "") + ".\n" +
+			takeOne + " " + beers(nextQty) + "\n\n"
+		}
+
+		if (qty == -1) song
+		else sing(qty - 1)(song + refrain) // tail recursion
+	}
+
+	implicit val headOfSong : String = ""
+
+	println(sing(99)) // implicit parameter
+
+}