FTS / gfal2 updates to support IPv6 vs. IPv4 monitoring for HTTP-TPC

• rely on RemoteConnections data from HTTP-TPC performance markers
  • progress with HTTP-TPC in DMC-1311
  • status of xroot protocol tracked in DMC-1016
• these data still not available in StoRM implementation
• available in dCache 6.2.28, XRootD 5.0, DPM 1.14.0, EOS, Echo

Add storage.*:/path tests in compliance testsuite