Give a local chat message/alert to lurkers who wish to use a nickname that is already in use

[Smidqe]

There's been few occasions with random 'hi' users which does implicate they attempted to select a username that was already in use/registered. It would be beneficial to let those users know if the nickname is already registered/in use

as per latest: I put in the nickname I wanted three times, and when I put in Hi suddenly it screws me