v2.0 Switch from UserParametr to script

Changes

1. Replace UserParametr to script: /usr/libexec/zabbix/disk_stat.sh
2. One version for all Linux distrib
3. Autodetect column version and switch to awk(if column not support json output)
4. Handle flush requests and time spent flushing(Kernel 5.5+)

v1.0 UserParametr

This is last commit with UserParametr