Provide a way to remotely trigger application restart

[this-Aditya]

It would be useful to have a mechanism to remotely trigger an application restart, so that we don’t need to directly contact participants to ask them to restart the app manually.

One possible approach is to integrate Firebase Cloud Messaging into pRMT and send notifications to participants, either individually or by groups. The notification could state something like “App stopped, click to restart”, and tapping it would restart the application.