ZABBIX 4.0 LTS : Install Zabbix Server on CentOS 7

Platform
- Zabbix Version 4.0 LTS
- OS CentOS 7
- Database MySQL (MariaDB)

Step to install :
1. Install Zabbix repository
2. Install Zabbix server, frontend, database
3. Setup root database
4. Create initial database
5. Configure the database for Zabbix server
6. Configure PHP for Zabbix frontend
7. Configure firewall
8. Configure selinux rule
9. Start zabbix server and frontend
10. Setup Zabbix frontend