index.js: some comments

index.js

@@ -1,7 +1,11 @@
 
 const express = require('express')
 const app = express()
+
+// if the content-type is application/json, the incoming POST body is parsed automatically
 app.use(express.json());
+
+// connect the plugin(s)
 app.use('/plugin', require('./plugin'))
 
 // catch 404 and forward to error handler