fix controller set body error

Author: capasky

lib/controller/controller.js

@@ -24,6 +24,16 @@ class Controller extends EventEmitter {
         this._filters = {};
         Object.assign(this, ctx);
         this.ctx = ctx;
+        Object.defineProperties(this, {
+            body: {
+                set(value) {
+                    ctx.body = value;
+                },
+                get() {
+                    return ctx.body;
+                }
+            }
+        });
     }
     /**
      * register filter(s) for specific action, the filter(s) will run before action execute