klick on selectes dates unselects it

.dockerignore added
mongo adapted to newest version
package.json: all debedencies updated

modules/mongointerface.js

@@ -16,7 +16,7 @@ let  COLLECTION = 'spritzschema'
     if (options.testing) {
         COLLECTION =  'spritzschema_test'
     }
-    const client = new MongoClient(MONGO_URL, { useUnifiedTopology: true })
+    const client = new MongoClient(MONGO_URL)
     try {
         await client.connect()
         if (cmd === 'getdata') {