**Use case**
ClickHouse as a web server becomes a viable scenario.
(At least in backoffice).

**Describe the solution you'd like**
Add this field.

**Additional context**
It's in question how to name it. The original HTTP specs has the famous typo in it and name it `referer`. While JavaScript has this typo fixed and name it `referrer`.

#include "HTTPHandler.h"
#include "HTTPHandlerFactory.h"
#include "HTTPHandlerRequestFilter.h"
#include <chrono>
#include <iomanip>
#include <Poco/File.h>
#include <Poco/Net/HTTPBasicCredentials.h>
#include <Poco/Net/HTTPServerRequest.h>
#include <Poco/Net/HTTPServerRequestImpl.h>
#include <Poco/Net/HTTPServerResponse.h>
#include <Poco/Net/HTTPRequestHandlerFactory.h>
#include <Poco/Net/NetException.h>
#include <ext/scope_guard.h>
#include <Core/ExternalTable.h>
#include <Common/StringUtils/StringUtils.h>
#include <Common/escapeForFileName.h>
#include <common/getFQDNOrHostName.h>
#include <Common/setThreadName.h>
#include <Common/SettingsChanges.h>
#include <Disks/StoragePolicy.h>
#include <Compression/CompressedReadBuffer.h>
#include <Compression/CompressedWriteBuffer.h>
#include <IO/ReadBufferFromIStream.h>
#include <IO/ReadBufferFromString.h>
#include <IO/WriteBufferFromString.h>
#include <IO/WriteBufferFromHTTPServerResponse.h>
#include <IO/WriteBufferFromFile.h>
#include <IO/WriteHelpers.h>