Support React v0.4 (while keeping BC)

Author: clue

composer.json

@@ -12,9 +12,9 @@
     ],
     "require": {
         "php": ">=5.3",
-        "react/promise": "~1",
-        "react/event-loop": "0.3.*",
-        "react/child-process": "0.3.*"
+        "react/promise": "~2.0|~1.0",
+        "react/event-loop": "~0.4.0|~0.3.0",
+        "react/child-process": "~0.4.0|~0.3.0"
     },
     "autoload": {
         "psr-4": { "Clue\\React\\Zenity\\": "src/" }