Auth: Add page to change password.

Configure launcher as a default return to address.

Use standard X-Forwarded-User instead of custom X-User header.
Add X-Forwarded-UserId header holding user unique identificator.

Change-Id: Ib2e6329ba9fb91d2cc9a86b0c5fc78898769e3b8
diff --git a/core/installer/cmd/welcome.go b/core/installer/cmd/welcome.go
index 30ed48f..d754ad3 100644
--- a/core/installer/cmd/welcome.go
+++ b/core/installer/cmd/welcome.go
@@ -88,7 +88,7 @@
 	if err != nil {
 		return err
 	}
-	s := welcome.NewServer(
+	s, err := welcome.NewServer(
 		welcomeFlags.port,
 		repoIO,
 		nsCreator,
@@ -97,6 +97,9 @@
 		welcomeFlags.loginAddr,
 		welcomeFlags.membershipsAddr,
 	)
+	if err != nil {
+		return err
+	}
 	s.Start()
 	return nil
 }