ChatRequest small fixes

[ibillingsley]

A few small bug fixes for the chat request module. There are separate commits but I put them on one branch.

• The default RemoveCommand_OK text had @RequesterName instead of @$RequesterName
• Using the !link command during a WIP or OST map would send the url of the previous map. Set it to empty string instead.
• Update the "queue is open/closed" text in the center panel when opening/closing queue.
• Moved the check for "already requested this session" below the check for "already in queue". The "already in queue" message is more useful, even though locking the queue is more expensive, most requests will have to do both checks anyway.

[hardcpp]

Hey, thanks for the MR!, can you add one last change? in CRConfig.cs, OnInit can you patch "@RequesterName" => "@$RequesterName" ?

[ibillingsley]

Done.