Update readme with information regarding shutdown

Author: jsumners

Readme.md

@@ -5,8 +5,8 @@ This module provides access to an Oracle database connection pool via the
 [oracledb](https://npm.im/oracledb) module. It decorates the [Fastify](https://fastify.io)
 instance with an `oracle` property that is a connection pool instance.
 
-When the Fastify server is shutdown, this plugin invokes the `.close()` on the
-connection pool.
+When the Fastify server is shutdown, this plugin invokes the `.close()` method
+on the connection pool.
 
 ## Example
 
@@ -27,6 +27,19 @@ fastify.get('/db_data', async function (req, reply) {
   await conn.close()
   return results
 })
+
+fastify.listen(3000, (err) => {
+  if (err) {
+    fastify.log.error(err)
+    // Manually close since Fastify did not boot correctly.
+    fastify.oracle.close()
+    process.exit(1)
+  }
+
+  // Initiate Fastify's shutdown procedure so that the plugin will
+  // automatically close the connection pool.
+  process.on('SIGTERM', fastify.close.bind(fastify))
+})
 ```
 
 ## Options