Revert "boost::system_error"

This reverts commit 41a4ea11631134d51e459a78ea30014df9145455.

lib/network/NetworkConnection.cpp

@@ -26,7 +26,7 @@ NetworkConnection::NetworkConnection(INetworkConnectionListener & listener, cons
 	{
 		socket->set_option(boost::asio::socket_base::send_buffer_size{bufferSize});
 	}
-	catch(const std::system_error & e)
+	catch(const boost::system::system_error & e)
 	{
 		logNetwork->error("error setting 'send buffer size' socket option: %s", e.what());
 	}
@@ -35,7 +35,7 @@ NetworkConnection::NetworkConnection(INetworkConnectionListener & listener, cons
 	{
 		socket->set_option(boost::asio::socket_base::receive_buffer_size{bufferSize});
 	}
-	catch(const std::system_error & e)
+	catch(const boost::system::system_error & e)
 	{
 		logNetwork->error("error setting 'receive buffer size' socket option: %s", e.what());
 	}

lobby/EntryPoint.cpp

@@ -39,7 +39,7 @@ int main(int argc, const char * argv[])
 	{
 		server.start(LISTENING_PORT);
 	}
-	catch (const std::system_error & e)
+	catch (const boost::system::system_error & e)
 	{
 		logGlobal->error("Failed to start server! Another server already uses the same port? Reason: '%s'", e.what());
 		return 1;