Registered Only Server

Implemented the ability to set the server to only allow registered
users.  Also updated client to reflect the log-in rejection as well as
put a check in place for the server to not start if db connection is not
available yet registration is required.

common/server_protocolhandler.cpp

@@ -345,6 +345,7 @@ Response::ResponseCode Server_ProtocolHandler::cmdLogin(const Command_Login &cmd
 		case NotLoggedIn: return Response::RespWrongPassword;
 		case WouldOverwriteOldSession: return Response::RespWouldOverwriteOldSession;
 		case UsernameInvalid: return Response::RespUsernameInvalid;
+		case RegistrationRequired: return Response::RespRegistrationRequired;
 		default: authState = res;
 	}