Fix org.getMembers() to 'wrap' returned users for post-populating

This fixes an issue introduced with PR #66 in commit fee02a3 - the
`getMembers()` method switched to using paging, but lost the code that
populated the users with a full set of values.

This commit just applies 'wrapping' to all users returned, so that methods
like `user.getCreatedAt()` can be called on returned users without throwing
a NullPointerException - the reference to 'root' allows the user objects to
populate themselves.

src/main/java/org/kohsuke/github/GHOrganization.java

@@ -105,7 +105,8 @@ public PagedIterator<GHUser> iterator() {
                 String filterParams = (filter == null) ? "" : ("?filter=" + filter);
                 return new PagedIterator<GHUser>(root.retrieve().asIterator(String.format("/orgs/%s/%s%s", login, suffix, filterParams), GHUser[].class)) {
                     @Override
-                    protected void wrapUp(GHUser[] page) {
+                    protected void wrapUp(GHUser[] users) {
+                        GHUser.wrap(users, root);
                     }
                 };
             }