[#1770] logger: Refactor Logger component

Make it store its internal `zap.Logger`'s level. Also, make all the
components to accept internal `logger.Logger` instead of `zap.Logger`; it
will simplify future refactor.

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

pkg/local_object_storage/writecache/generic_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/nspcc-dev/neofs-node/pkg/local_object_storage/internal/storagetest"
+	"github.com/nspcc-dev/neofs-node/pkg/util/logger"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap/zaptest"
 )
@@ -20,7 +21,7 @@ func TestGeneric(t *testing.T) {
 		dir := filepath.Join(t.Name(), strconv.Itoa(n))
 		require.NoError(t, os.MkdirAll(dir, os.ModePerm))
 		return New(
-			WithLogger(zaptest.NewLogger(t)),
+			WithLogger(&logger.Logger{Logger: zaptest.NewLogger(t)}),
 			WithFlushWorkersCount(2),
 			WithPath(dir))
 	}