Qr-code display for safebag and backdrop around existing ones

[AnoldGH]

• Adds qr-code display for safebag
• Wraps qr-code displays for certificate and trust anchors so that it's more friendly to users in general
• [Next step] Adds qr-reader for certificate and safebag

[zjkmxy]

Unfortunately adding QR code for safebags on the website does not help. The safebag is obtained somewhere and then inputed to workspace for bootstrap. So the most important part is that the somewhere should support QR cde display.

[AnoldGH]

Unfortunately adding QR code for safebags on the website does not help. The safebag is obtained somewhere and then inputed to workspace for bootstrap. So the most important part is that the somewhere should support QR cde display.

I see. That makes very sense.

This update also wrapped backdrop components around existing QR displays, so they are shown only when the button is pressed and in full-screen. This I think makes using QR codes much more friendly for mobile users. Let me know if I should create a separate PR for it.

[zjkmxy]

Let me know if I should create a separate PR for it.

If that is the case, let me review it and get it merged. No need for separate PR.

[zjkmxy]

LGTM