Zabbix

........S. [ZBXNEXT-1804] changed active agent, sender, proxy (old) historical data processing to share code with new proxy data processing
                          Basically the process_mass_data() function that 'did everything' was split into 3 logical parts:
                             1) data parsing (parse json data into agent values and host keys)
                             2) data validation (check corresponding item can accept the parsed data)
                             3) data processing (add the validated data to history cache and update items in configuration cache)