[#145] sdk/object: Implement Object deserialization function

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

pkg/object/object.go

@@ -37,3 +37,14 @@ func (o *Object) ToV2() *object.Object {
 
 	return nil
 }
+
+// FromBytes restores Object instance from a binary representation.
+func FromBytes(data []byte) (*Object, error) {
+	oV2 := new(object.Object)
+
+	if err := oV2.StableUnmarshal(data); err != nil {
+		return nil, err
+	}
+
+	return NewFromV2(oV2), nil
+}