Add a random module.

test/random/new.wren

@@ -0,0 +1,12 @@
+import "random" for Random
+
+var random = Random.new()
+
+var correct = 0
+for (i in 1..100) {
+  var n = random.float()
+  if (n >= 0) correct = correct + 1
+  if (n < 1) correct = correct + 1
+}
+
+System.print(correct) // expect: 200