get rid of 0.11

Makefile

@@ -9,7 +9,7 @@ ifeq ($(findstring io.js, $(shell which node)),)
 endif
 
 ifeq (node, $(BIN))
-	FLAGS = --harmony-generators
+	FLAGS = --harmony
 endif
 
 REQUIRED = --require should --require should-http

Readme.md

@@ -21,7 +21,7 @@ $ npm install koa
 
   Koa is supported in all versions of [iojs](https://iojs.org) without any flags.
 
-  To use Koa with node, you must be running __node 0.11.16__ or higher for generator and promise support, and must run node(1)
+  To use Koa with node, you must be running __node 0.12.0__ or higher for generator and promise support, and must run node(1)
   with the `--harmony-generators` or `--harmony` flag.
 
 ## Community

package.json

@@ -53,7 +53,7 @@
     "test-console": "^0.7.1"
   },
   "engines": {
-    "node": ">= 0.11.16",
+    "node": ">= 0.12.0",
     "iojs": ">= 1.0.0"
   },
   "files": [