Merge pull request #26 from AlexWangD/master

Fix a bug about the wrong serializedName of Permission.READWRITE.

Author: hrchu

src/main/java/org/twonote/rgwadmin4j/model/SubUser.java

@@ -77,7 +77,7 @@ public enum Permission {
     @SerializedName("write")
     WRITE,
 
-    @SerializedName("readwrite")
+    @SerializedName("read-write")
     READWRITE,
 
     @SerializedName(