Refactor/resource firewall filter

[maksym-nazarenko]

No description provided.

[ddelnano]

Exciting to see the final legacy resources migrated to the plugin framework! Thanks for moving so quickly through these and all the great scaffolding work that made this transition easier.

[maksym-nazarenko]

I'm really enjoying contributing to this project ;)

[teadur]

kube-clouds fork seems to have way fancier firewall, maybe the option set could be migrated to this provider ?
https://github.com/kube-cloud/terraform-provider-mikrotik/blob/master/client/firewall_rule.go
Do i understand correctly that neither of them support ipv6 ?

[maksym-nazarenko]

@teadur the resources were created with minimal option set in mind, as complete support requires much more work.
If you think there are missing parts, which could help you, feel free to create an issue with such request - I'll be glad to evaluate it.