add single files, secure server, hello world

helloworld.dart

@@ -0,0 +1,22 @@
+#!/usr/local/bin/dart
+
+void main() {
+
+  var sb = new StringBuffer();
+  sb..write('Hello ')
+    ..write('world ')
+    ..write('!');
+
+  print(sb.toString());
+
+  for (int i = 0; i < 5; i++) {
+    print('Hello:  ${i}');
+  }
+
+  var arr = [];
+  for (int i = 0; i < 10; i++) {
+    arr.add(i);
+  }
+  print(arr);
+  print(arr.join(':'));
+}