WPPilot 1.17.1 — clearer WPPilot Cloud connection errors

• Fixed: when WPPilot Cloud could not finish connecting because its test request to this site failed, the Connect screen showed only "verification_failed". It now names the reason (for example verification_failed-unauthorized_403 when a firewall or security plugin refuses the request, or protocol_200 when a challenge page or redirect answers instead) and says what to change. Connection Doctor does not test the token WPPilot Cloud uses, so it can pass while this check fails.