[#18] Add AddPeer and UpdatePeer morph events

Signed-off-by: Alex Vanin <alexey@nspcc.ru>

pkg/morph/event/netmap/add_peer.go

@@ -0,0 +1,37 @@
+package netmap
+
+import (
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
+	"github.com/nspcc-dev/neofs-node/pkg/morph/client"
+	"github.com/nspcc-dev/neofs-node/pkg/morph/event"
+	"github.com/pkg/errors"
+)
+
+type AddPeer struct {
+	node []byte
+}
+
+// MorphEvent implements Neo:Morph Event interface.
+func (AddPeer) MorphEvent() {}
+
+func (s AddPeer) Node() []byte {
+	return s.node
+}
+
+func ParseAddPeer(prms []smartcontract.Parameter) (event.Event, error) {
+	var (
+		ev  AddPeer
+		err error
+	)
+
+	if ln := len(prms); ln != 1 {
+		return nil, event.WrongNumberOfParameters(1, ln)
+	}
+
+	ev.node, err = client.BytesFromStackParameter(prms[0])
+	if err != nil {
+		return nil, errors.Wrap(err, "could not get integer epoch number")
+	}
+
+	return ev, nil
+}