v0.2 - for IPFire 2.27 CU 170+

• Add DHCP client: # active clients (contributed by @StackKorora)
• Add Captive Portal: # active leases (contributed by @StackKorora)
• Removed entropy, rdrand and rngd checks
• Migrated to new zabbix_agentd ipfire addon (IPFire 2.27 CU 170):
  • Removed agent .conf files now natively included in addon
  • Adapt ipfire_services.pl to use pakfire internal procedures
• Applied latest Zabbix template guidelines (tags, namings, ...)
• Removed Zabbix 4.x support
• Removed Zabbix 5.0/5.2 support
• Add support for Zabbix 5.4
• Add support for Zabbix 6.0