Add SQLite database storage backend

base/database/storage/sqlite/migrations/0_settings.sql

@@ -0,0 +1,7 @@
+-- +migrate Up
+-- SQL in section 'Up' is executed when this migration is applied
+PRAGMA auto_vacuum = INCREMENTAL; -- https://sqlite.org/pragma.html#pragma_auto_vacuum
+
+-- +migrate Down
+-- SQL section 'Down' is executed when this migration is rolled back
+PRAGMA auto_vacuum = NONE; -- https://sqlite.org/pragma.html#pragma_auto_vacuum

base/database/storage/sqlite/migrations/1_initial.sql

@@ -0,0 +1,19 @@
+-- +migrate Up
+-- SQL in section 'Up' is executed when this migration is applied
+CREATE TABLE records (
+    key TEXT PRIMARY KEY,
+
+    format SMALLINT NOT NULL,
+    value  BLOB NOT NULL,
+
+    created    BIGINT NOT NULL,
+    modified   BIGINT NOT NULL,
+    expires    BIGINT DEFAULT 0 NOT NULL,
+    deleted    BIGINT DEFAULT 0 NOT NULL,
+    secret     BOOLEAN DEFAULT FALSE NOT NULL,
+    crownjewel BOOLEAN DEFAULT FALSE NOT NULL
+);
+
+-- +migrate Down
+-- SQL section 'Down' is executed when this migration is rolled back
+DROP TABLE records;