These fixes are needed to make the provider work with master again.
These are still some issues, but they seem not to be related to the
provider, but the changes in `helper/schema`.
This goes for the normal firewall, the egress firewall and the network
ACL.
USE WITH CAUTION! When setting `managed = true` in your config, it
means it will delete all firewall rules that are not in your config, so
unknown to TF.
Also adding the new `cloudstack_egress_firewall` resource with this
commit and updating go-cloudstack to the latest API version (v4.4)