Update existing screens when syncing from Sketch plugin

[aentan]

I only started using the Sketch plugin as my company made the switch to Google Team Drives and Marvel does not support that yet, so decided to give the plugin a go. All my current screens are not sync with plugin.

When I try to sync a screen from plugin, it just adds a new screen to my project. Obviously I would prefer that screens with same name would just update. I don't want to redo all my hotspots.