Addition of auto-key usage function with C key + contact

[p]We were incredibly foolish, possessing only a culture so primitive that during the era of Pangaea, the best we could manage was competing with horseshoe crabs brought by staff members.[/p][p]Even now, after the continents split apart and we ended up living on strange island, we still can't keep up with the development and optimization of civilization.[/p][p]For a feature that could be implemented in five minutes, it took nearly eight years before anyone noticed it needed to be implemented.[/p][p](Honestly, I doubt there were many situations where you'd press C while making contact.[/p][p]Since it probably wouldn't interfere much with other controls, we didn't implement a toggle function this time.[/p][p]If it becomes inconvenient later, we'll add an option to the config to toggle C-key unlocking on/off.)[/p]