Send buffered packets from print to either ESP8266WebServer or WiFiClient on ESP8266

Bufferedpackets.h

/*
	Send out buffered packets to ESP8266WebServer or WiFiClient on ESP8266 on Arduino IDE. 
See https://github.com/bblanchon/ArduinoJson/issues/166

exmaple of use with arudino json
    size_t jsonlength = root.measureLength();
    HTTP.setContentLength(jsonlength);
    HTTP.send(200, "text/json" );
    BufferedPrint<HTTP_DOWNLOAD_UNIT_SIZE> proxy(HTTP);
    root.printTo(proxy);
    proxy.flush();
OR
    size_t jsonlength = root.measureLength();
    HTTP.setContentLength(jsonlength);
    HTTP.send(200, "text/json" );
    WiFiClient client = HTTP.client(); 
    BufferedPrint<HTTP_DOWNLOAD_UNIT_SIZE> proxy(client);
    root.printTo(proxy);
    proxy.flush();
*/
template<size_t CAPACITY>
class BufferedPrint : public Print
{
public:
	BufferedPrint(ESP8266WebServer & HTTP) : _size(0)
	{
		_client = HTTP.client();
	}
	
	BufferedPrint(WiFiClient & client) : _client(client), _size(0)
	{
	}

	~BufferedPrint() {
		_client.stop(); 
	}

	virtual size_t write(uint8_t c)
	{
		_buffer[_size++] = c;

		if (_size + 1 == CAPACITY)
		{
			flush();
		}
	}

	void flush()
	{
		 _client.write( (const char *)_buffer, _size);
		 _size = 0;
	}

private:
	WiFiClient _client;
	size_t _size;
	char _buffer[CAPACITY];
};