Added functionality for server restart when client certificate updated

This PR relates to issue on core: https://github.com/jembi/openhim-core-js/issues/137.
When i user updates a clients' certificate, the user is informed a server restart is needed. They can do it manually later or click the restart button to request for the servers to be restarted
Perhaps instead of the Or manually restart later text we could add a blue button that says 'I'll manually restart later', when this button is clicked the alert disappears.