Update composer to tagged psr/http-message

composer.json

@@ -13,7 +13,7 @@
     ],
     "require": {
         "php": ">=5.4.0",
-        "psr/http-message": "dev-master"
+        "psr/http-message": "~0.11"
     },
     "require-dev": {
         "phpunit/phpunit": "~4.6"

composer.lock

@@ -1,28 +1,25 @@
 {
     "_readme": [
         "This file locks the dependencies of your project to a known state",
-        "Read more about it at http://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
+        "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#composer-lock-the-lock-file",
         "This file is @generated automatically"
     ],
-    "hash": "c949a9b62aff4159f1ea8da17f38f508",
+    "hash": "4b858928ad73a2b95a95738740f8305e",
     "packages": [
         {
             "name": "psr/http-message",
-            "version": "dev-master",
+            "version": "0.11.0",
             "source": {
                 "type": "git",
                 "url": "https://github.com/php-fig/http-message.git",
-                "reference": "85d63699f0dbedb190bbd4b0d2b9dc707ea4c298"
+                "reference": "809419e498a388dfa7ef6898392431e5911a0289"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/php-fig/http-message/zipball/85d63699f0dbedb190bbd4b0d2b9dc707ea4c298",
-                "reference": "85d63699f0dbedb190bbd4b0d2b9dc707ea4c298",
+                "url": "https://api.github.com/repos/php-fig/http-message/zipball/809419e498a388dfa7ef6898392431e5911a0289",
+                "reference": "809419e498a388dfa7ef6898392431e5911a0289",
                 "shasum": ""
             },
-            "require": {
-                "php": ">=5.3.0"
-            },
             "type": "library",
             "extra": {
                 "branch-alias": {
@@ -31,7 +28,7 @@
             },
             "autoload": {
                 "psr-4": {
-                    "Psr\\Http\\Message\\": "src/"
+                    "Psr\\Http\\Message\\": "src"
                 }
             },
             "notification-url": "https://packagist.org/downloads/",
@@ -53,7 +50,7 @@
                 "request",
                 "response"
             ],
-            "time": "2015-05-04 20:22:00"
+            "time": "2015-05-04 20:20:08"
         }
     ],
     "packages-dev": [
@@ -1017,9 +1014,7 @@
     ],
     "aliases": [],
     "minimum-stability": "stable",
-    "stability-flags": {
-        "psr/http-message": 20
-    },
+    "stability-flags": [],
     "prefer-stable": false,
     "prefer-lowest": false,
     "platform": {