Update references to 0.3, update lock file

Author: igorw

composer.json

@@ -7,16 +7,16 @@
         "php": ">=5.3.3",
         "guzzle/http": "2.8.*",
         "guzzle/parser": "2.8.*",
-        "react/socket": "0.2.*",
-        "react/dns": "0.2.*"
+        "react/socket": "0.3.*",
+        "react/dns": "0.3.*"
     },
     "autoload": {
         "psr-0": { "React\\HttpClient": "" }
     },
     "target-dir": "React/HttpClient",
     "extra": {
         "branch-alias": {
-            "dev-master": "0.2-dev"
+            "dev-master": "0.3-dev"
         }
     }
 }