Add a very simple low cost database

src/db.h

@@ -0,0 +1,7 @@
+#pragma once
+
+#include <stdint.h>
+
+uint8_t *db_search (uint8_t **, uint8_t *);
+int      db_insert (uint8_t **, uint8_t *);
+int      db_remove (uint8_t **, uint8_t *);