Update to stable reactphp/http v1.8.0

Author: clue

composer.json

@@ -20,8 +20,8 @@
         "php": ">=5.3",
         "clue/json-stream": "^0.1",
         "react/event-loop": "^1.2",
-        "react/http": "^1.8@dev || ^1.7",
-        "react/promise": "^3@dev || ^2.0 || ^1.1",
+        "react/http": "^1.8",
+        "react/promise": "^3 || ^2.0 || ^1.1",
         "react/promise-stream": "^1.4",
         "react/socket": "^1.12",
         "react/stream": "^1.2",