App crashes when there is not external activities that matches intent

[danilo04]

Avoid crashing when calling external activities and the phone doesn't have any matching activity.

Expected

Show a Toast that the phone doesn't have a matching activity.

Observed

Crashes. For example, this crash when exporting notes:

No Activity found to handle Intent { act=android.intent.action.CREATE_DOCUMENT cat=[android.intent.category.OPENABLE] typ=application/json (has extras) }

Reproduced

Note: the device doesn't have to have a file manager app.

1. Go to Settings
2. Tap on Export Notes
3. See the app crashes

Device Make: Motorola
Device Model: Moto G 2014
Android Version: 7.1.2
Simplenote Version: 2.19