Add Dart support

demo/kitchen-sink/docs/dart.dart

@@ -0,0 +1,58 @@
+main() {
+  print('Hello World!');
+}
+
+
+int fib(int n) => (n > 1) ? (fib(n - 1) + fib(n - 2)) : n;
+main() {
+  print('fib(20) = ${fib(20)}');
+}
+/*asd
+asdad
+*/
+0.67
+77
+.86
+
+#import("http://dartwatch.com/myOtherLibrary.dart");
+#import("myOtherLibrary.dart", prefix:"lib1");
+
+"""asdasdads
+asdadsadsasd
+asdasdasdad"""
+ 
+'23424'
+
+0x234
+
+foo is bar
+
+int x = 4 << 10 
+// Create a class for Point.
+class Point {
+ 
+  // Final variables cannot be changed once they are assigned.
+  // Create two instance variables.
+  final num x, y;
+ 
+  // A constructor, with syntactic sugar for setting instance variables.
+  Point(this.x, this.y);
+ 
+  // A named constructor with an initializer list.
+  Point.origin() : x = 0, y = 0;
+ 
+  // A method.
+  num distanceTo(Point other) {
+    var dx = x - other.x;
+    var dy = y - other.y;
+    return sqrt(dx * dx + dy * dy);
+  }
+}
+ 
+ // Check for null.
+var unicorn;
+assert(unicorn == null);
+
+// Check for NaN.
+var iMeantToDoThis = 0/0;
+assert(iMeantToDoThis.isNaN());