add Context#cookies support. Closes #7

need to add signing support in there as well

examples/cookies.js

@@ -0,0 +1,16 @@
+
+var http = require('http');
+var koa = require('..');
+var app = koa();
+
+app.use(function(){
+  return function *(){
+    if ('/favicon.ico' == this.path) return;
+    var n = ~~this.cookies.get('view') || 1;
+    this.cookies.set('view', n + 1);
+    this.body = n + ' views';
+  }
+});
+
+app.listen(3000);
+console.log('listening on port 3000');

lib/application.js

@@ -7,6 +7,7 @@ var debug = require('debug')('koa:app');
 var Emitter = require('events').EventEmitter;
 var compose = require('koa-compose');
 var context = require('./context');
+var Cookies = require('cookies');
 var Stream = require('stream');
 var http = require('http');
 var co = require('co');
@@ -217,5 +218,6 @@ function createContext() {
     this.app = app;
     this.req = req;
     this.res = res;
+    this.cookies = new Cookies(req, res);
   }
 }

package.json

@@ -28,7 +28,8 @@
     "qs": "0.6.5",
     "fresh": "0.2.0",
     "negotiator": "0.2.7",
-    "koa-compose": "1.0.0"
+    "koa-compose": "1.0.0",
+    "cookies": "~0.3.6"
   },
   "devDependencies": {
     "bytes": "*",