feat(connect): add junction example

Author: azu

src/connect/junction-example.js

@@ -0,0 +1,25 @@
+"use strict";
+import Junction from "./junction";
+import assert from "power-assert";
+let junction = new Junction();
+junction.use(function toUpperCase(res, next) {
+    res.value = res.value.toUpperCase();
+    next();
+});
+junction.use(function exclamationMark(res, next) {
+    res.value = res.value + "!";
+    next();
+});
+junction.use(function (error, res, next) {
+    console.error(error.stack);
+    next();
+});
+
+let text = "hello world";
+junction.process(text, function (error, result) {
+    if (error) {
+        console.error(error);
+    }
+    let value = result.value;
+    assert.equal(value, "HELLO WORLD!");
+});