make sure the hostname is correct

Our server effectively has two hostnames, fws-hub and mellte (the name of a Welsh river). The hostname we want to give out to everyone is fws-hub, but everything on the server was set to call itself mellte. This was getting picked up by apache and was causing pages to end up referring to mellte not fws-hub. Unfortunately we'd registered for recaptcha (used for user signup) as fws-hub and this was getting broken because it didn't match so new users couldn't sign up.