[REQ] SpawnTest mode

[HangTimeQW]

This is a feature request not a bug. I would like a prewar feature whereby if you move over a spawn point you receive some sort of alert like a message stuffed to client. This would be useful for practicing safe routes for moving around maps without getting telefragged by respawning players, and especially useful on maps with no visual indicators of the spawn points.

There is already a feature to indicate spawn locations via keys/scrags but it's not clear exactly where the threshold is to get telefragged.

This feature might be a bit spammy so it would be good if players could toggle it on a per-client basis via kflags or something.