Feat linux firewall support (#805)

Update the client's engine to apply firewall rules received from the manager (results of ACL policy).

client/internal/acl/manager_create.go

@@ -0,0 +1,27 @@
+//go:build !linux
+
+package acl
+
+import (
+	"fmt"
+	"runtime"
+
+	"github.com/netbirdio/netbird/client/firewall"
+	"github.com/netbirdio/netbird/client/firewall/uspfilter"
+)
+
+// Create creates a firewall manager instance
+func Create(iface iFaceMapper) (manager *DefaultManager, err error) {
+	if iface.IsUserspaceBind() {
+		// use userspace packet filtering firewall
+		fm, err := uspfilter.Create(iface)
+		if err != nil {
+			return nil, err
+		}
+		return &DefaultManager{
+			manager:    fm,
+			rulesPairs: make(map[string][]firewall.Rule),
+		}, nil
+	}
+	return nil, fmt.Errorf("not implemented for this OS: %s", runtime.GOOS)
+}