extend alert message box to add dismissible button
extend alert message box to add dismissible button

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