VOL-1497 : Add more control to kv/memory access

- Added kv locking mechanism (etcd only)
- (watch) control path access whenever possible
- (watch) use a transaction for updates and merge with memory
- cleaned up vendoring
- misc changes to fix exceptions found along the way

Amendments:

- Copyright header got removed in auto-generated file
- Changed default locking to false for KV list operation
- Updated backend api to allow the passing of locking parameter

Change-Id: Ie1a55d3ca8b9d92ae71a85ce42bb22fcf1419e2c
diff --git a/vendor/golang.org/x/sys/unix/asm_netbsd_arm64.s b/vendor/golang.org/x/sys/unix/asm_netbsd_arm64.s
new file mode 100644
index 0000000..6f98ba5
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/asm_netbsd_arm64.s
@@ -0,0 +1,29 @@
+// Copyright 2019 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo
+
+#include "textflag.h"
+
+//
+// System call support for ARM64, NetBSD
+//
+
+// Just jump to package syscall's implementation for all these functions.
+// The runtime may know about them.
+
+TEXT	·Syscall(SB),NOSPLIT,$0-56
+	B	syscall·Syscall(SB)
+
+TEXT	·Syscall6(SB),NOSPLIT,$0-80
+	B	syscall·Syscall6(SB)
+
+TEXT	·Syscall9(SB),NOSPLIT,$0-104
+	B	syscall·Syscall9(SB)
+
+TEXT	·RawSyscall(SB),NOSPLIT,$0-56
+	B	syscall·RawSyscall(SB)
+
+TEXT	·RawSyscall6(SB),NOSPLIT,$0-80
+	B	syscall·RawSyscall6(SB)