**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`.

{DataTypeFactory::instance().get("IPv6"),   "address"},
        {std::make_shared<DataTypeUInt16>(),        "port"},
        {std::make_shared<DataTypeString>(),        "initial_user"},
        {std::make_shared<DataTypeString>(),        "initial_query_id"},
        {DataTypeFactory::instance().get("IPv6"),   "initial_address"},
        {std::make_shared<DataTypeUInt16>(),        "initial_port"},
        {std::make_shared<DataTypeUInt8>(),         "interface"},
        {std::make_shared<DataTypeString>(),        "os_user"},
        {std::make_shared<DataTypeString>(),        "client_hostname"},
        {std::make_shared<DataTypeString>(),        "client_name"},
        {std::make_shared<DataTypeUInt32>(),        "client_revision"},
        {std::make_shared<DataTypeUInt32>(),        "client_version_major"},
        {std::make_shared<DataTypeUInt32>(),        "client_version_minor"},
        {std::make_shared<DataTypeUInt32>(),        "client_version_patch"},
        {std::make_shared<DataTypeUInt8>(),         "http_method"},
        {std::make_shared<DataTypeString>(),        "http_user_agent"},
        {std::make_shared<DataTypeString>(),        "forwarded_for"},
        {std::make_shared<DataTypeString>(),        "quota_key"},
        {std::make_shared<DataTypeUInt32>(),        "revision"},
        {std::make_shared<DataTypeArray>(std::make_shared<DataTypeString>()), "ProfileEvents.Names"},
        {std::make_shared<DataTypeArray>(std::make_shared<DataTypeUInt64>()), "ProfileEvents.Values"}
    };
}
void QueryThreadLogElement::appendToBlock(MutableColumns & columns) const
{
    size_t i = 0;
    columns[i++]->insert(DateLUT::instance().toDayNum(event_time));
    columns[i++]->insert(event_time);
    columns[i++]->insert(event_time_microseconds);
    columns[i++]->insert(query_start_time);