Fix requirements.

Author: mekras

Diff for: composer.json

@@ -13,12 +13,12 @@
     "require": {
         "php": ">=5.5",
         "ext-curl": "*",
-        "php-http/httplug": "^1.0.0-alpha2",
+        "php-http/httplug": "1.0.0-alpha2",
         "php-http/message-factory": "^0.4@dev"
     },
     "require-dev": {
         "guzzlehttp/psr7": "^1.0",
-        "php-http/adapter-integration-tests": "dev-master",
+        "php-http/adapter-integration-tests": "dev-master#7c681907547e24b26f352bc48444527c28bfc524",
         "php-http/discovery": "^0.3",
         "phpunit/phpunit": "^4.8@stable",
         "zendframework/zend-diactoros": "^1.0"