Encourage export of identity after creating it

[audax]

After I create an identity, I want the application to prompt me to export my identity.

I may forget to export it and clear the application data (for example by uninstalling the application), then I lose my files.

[thechauffeur]

First we must decide on how this should be done. E.g. we could introduce a feature to securely store and restore an identity via Box + access to Qabel account. If there is an issue for this already we should reference these two issues.