epee: don't send the body of the response to a HEAD HTTP request

According to the HTTP spec: "The HEAD method is identical to GET
except that the server MUST NOT return a message-body in the
response".

contrib/epee/include/net/http_protocol_handler.inl

@@ -547,7 +547,7 @@ namespace net_utils
     LOG_PRINT_L3("HTTP_RESPONSE_HEAD: << \r\n" << response_data);
 		
 		m_psnd_hndlr->do_send((void*)response_data.data(), response_data.size());
-		if(response.m_body.size())
+		if(response.m_body.size() && (query_info.m_http_method != http::http_method_head))
 			m_psnd_hndlr->do_send((void*)response.m_body.data(), response.m_body.size());
 		return res;
 	}