add generic url signer
add generic url signer

tcspain/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb,DiamondLightSource/SynchWeb,DiamondLightSource/SynchWeb,tcspain/SynchWeb