Consumer app crashes if there is no network

[chrishobcroft]

Summary

Consumer app crashes if there is no network. It shows "The Paywall Page" for a brief moment, but then disappears.

Steps to reproduce

1. Switch device to airplane mode
2. Launch app
3. Observe paywall page appear, with QR code, user's address, and on-device information about the app
4. Observe the app crash.

Expected behaviour

At step 3, I expect the paywall page to still appear, and to show the user some information about the app, even if they can't actually use it to pay-to-play.

1. This would allow people to at least learn about the app when offline, to see that they have a wallet, to experience the UX

2. This would also allow users to receive credit top-up when offline - their balance being updated next time they have an internet connection.

[chrishobcroft]

Verified in the code submitted in the PR, closing.