add co example

examples/co.js

@@ -0,0 +1,22 @@
+
+var koa = require('..');
+var fs = require('co-fs');
+var app = koa();
+
+// read docs/*.md in parallel
+// and return a joined response
+
+app.use(function(){
+  return function *(){
+    var paths = yield fs.readdir('docs');
+
+    var files = yield paths.map(function(path){
+      return fs.readFile('docs/' + path, 'utf8');
+    });
+
+    this.type = 'markdown';
+    this.body = files.join(', ');
+  }
+});
+
+app.listen(3000);

package.json

@@ -20,7 +20,6 @@
     "rack"
   ],
   "repository": "koajs/koa",
-  "author": "",
   "license": "MIT",
   "dependencies": {
     "co": "1.5.1",
@@ -35,7 +34,8 @@
     "bytes": "*",
     "should": "1.2.2",
     "mocha": "1.12.0",
-    "supertest": "0.7.1"
+    "supertest": "0.7.1",
+    "co-fs": "~1.0.1"
   },
   "engines": {
     "node": "> 0.11.4"