[Feature Request] Allow changing the name of the backup directory

[zevlee]

Currently, the backup directory on desktop has an immutable name of "Standard Notes Backups" with no way to change it. This causes a problem when dealing with systems where white space is not allowed in file and directory names.

Proposed solution: Have the application place the backup files directly in the chosen backup location rather than creating a new "Standard Notes Backups" directory and moving the files there.