fix(pam): pam account registration integration (#263)

This ensures this is inserted at the correct place inside the pam stack.
Use default=ignore to let the registration pass if we can't connect to
authd.

UDENG-2495

debian/pam-configs/authd

@@ -5,8 +5,9 @@ Priority: 280
 Auth-Type: Primary
 Auth:
 	[success=end default=ignore]	pam_go_loader.so pam_authd.so
+Account-Type: Additional
 Account:
-	[default=bad success=ok user_unknown=ignore]	pam_go_loader.so pam_authd.so
+	[default=ignore success=ok user_unknown=ignore]	pam_go_loader.so pam_authd.so
 Password-Type: Primary
 Password:
 	sufficient			pam_go_loader.so pam_authd.so