**Use case**

For creating external data dictionary with settings (url, headers, etc.) from config.xml `<named_collections>`  for HTTP sources.
This is to allow updating per environment test, staging, prod without updating `CREATE DICTIONARY` statement, values set externally.

**Describe the solution you'd like**

Add HTTP source options as currently available for PostgreSQL, MySQL, S3 and Kafka:
https://clickhouse.com/docs/en/operations/named-collections/
keys should be `url`, `user`,`password`, `headers`.

**Describe alternatives you've considered**

use different data source for named collections.
use custom settings.

cc: @kssenii 

#include "HTTPDictionarySource.h"
#include <Formats/formatBlock.h>
#include <IO/ConnectionTimeouts.h>
#include <IO/ConnectionTimeoutsContext.h>
#include <IO/ReadWriteBufferFromHTTP.h>
#include <IO/WriteBufferFromOStream.h>
#include <IO/WriteBufferFromString.h>
#include <IO/WriteHelpers.h>
#include <Processors/Formats/IInputFormat.h>
#include <Interpreters/Context.h>
#include <Poco/Net/HTTPRequest.h>
#include <Common/logger_useful.h>
#include "DictionarySourceFactory.h"
#include "DictionarySourceHelpers.h"
#include "DictionaryStructure.h"
#include "registerDictionaries.h"
namespace DB
{
namespace ErrorCodes
{
    extern const int LOGICAL_ERROR;
}
static const UInt64 max_block_size = 8192;
HTTPDictionarySource::HTTPDictionarySource(