[#371] Support recent changes in NeoFS API protocol

Support:
  * new status codes (object, container, session);
  * object `Lock` message;
  * different signature schemes.

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

status/test/codes.go

@@ -0,0 +1,28 @@
+package statustest
+
+import (
+	"testing"
+
+	"github.com/nspcc-dev/neofs-api-go/v2/status"
+	"github.com/stretchr/testify/require"
+)
+
+// TestCodes checks mapping of status codes to the numbers.
+// Args must be pairs (status.Code, int).
+func TestCodes(t *testing.T,
+	localizer func(*status.Code) bool,
+	globalizer func(code *status.Code),
+	vals ...interface{},
+) {
+	for i := 0; i < len(vals); i += 2 {
+		c := vals[i].(status.Code)
+		cp := c
+
+		globalizer(&cp)
+		require.True(t, cp.EqualNumber(uint32(vals[i+1].(int))), c)
+
+		require.True(t, localizer(&cp), c)
+
+		require.Equal(t, cp, c, c)
+	}
+}