Various changes: Fixing namespace and some additions to Player.cs

[SrLicht]

• Remove unused using
• Fixing namespace in Args
• Added a property to get or set the distance at which other players can see player information.
• Added small description of what you can do with Player.PlayerInfo
• Added a property to get the player's body armor (if they have one)
• Renamed Player.ReceiveHint to Player.ShowHint
  • Since it's a big update and it's going to break a lot of things, putting some logic to the name of the method with which we send a hint to the player sounds good to me.