message: Add !unlink to admin_room.md
diff: @@ -99,7 +99,7 @@ commands are reserved for bridge administrators, which can be configured in the
  ### `!plumb`
  -`!feature !room:example.com irc.network.net #channel`
  +`!plumb !room:example.com irc.network.net #channel`
  *This command only works for bridge administrators*
  @@ -110,6 +110,17 @@ aware of your actions.
  You must invite the bridge bot into the Matrix room for this to work.
  +### `!unlink`
  +
  +`!unlink !room:example.com irc.network.net #channel`
  +
  +*This command only works for moderators of a bridged Matrix room and bridge administrators*
  +
  +This command allows you to unlink a IRC channel from a room without using the HTTP provisioning API. For bridge
  +administrators this command does NOT validate that you have permission to do this on the IRC channel so please
  +take care to ensure that the IRC channel is aware of your actions.
  +
  +
  ### `!help`
  Prints a list of commands for the bridge.
  