Add initial SQLite-backed state implementation

This contains the implementation of (most) container functions,
with stubs for all pod and volume functions. Presently accessed
via environment variable only for testing purposes.

Signed-off-by: Matt Heon <mheon@redhat.com>

vendor/github.com/mattn/go-sqlite3/sqlite3_opt_preupdate.go

@@ -0,0 +1,20 @@
+// Copyright (C) 2019 G.J.R. Timmer <gjr.timmer@gmail.com>.
+// Copyright (C) 2018 segment.com <friends@segment.com>
+//
+// Use of this source code is governed by an MIT-style
+// license that can be found in the LICENSE file.
+
+// +build cgo
+
+package sqlite3
+
+// SQLitePreUpdateData represents all of the data available during a
+// pre-update hook call.
+type SQLitePreUpdateData struct {
+	Conn         *SQLiteConn
+	Op           int
+	DatabaseName string
+	TableName    string
+	OldRowID     int64
+	NewRowID     int64
+}