[1.1]Added permissions. By default, all players can use the command, but if you want to restrict it, you can turn off the SignPlacard permissions with a permission management plugin, for example.
Permissions:
signPlacard.* - All SignPlacard permissions are granted.
signPlacard.commands - You will be granted all permissions for SignPlacard commands.(/spc set,/spc use,/spc show)