Fixes; Builtins; Testing in the interpreter

std/impl/error.ts

@@ -0,0 +1,20 @@
+/// <reference path="../../assembly.d.ts" />
+
+@global()
+class Error {
+
+  message: string;
+
+  constructor(message: string) {
+    this.message = message;
+  }
+}
+
+@global()
+class RangeError extends Error {}
+
+@global()
+class ReferenceError extends Error {}
+
+@global()
+class TypeError extends Error {}