Improve instructions on persistence
- Restructure all persistence instructions [72]
- Try to remove bits of persistence instructions [72]
- Simplify explanation of Read-Only
- Add partial screenshot to Applications menu [96] (this one can be done later)
- Add screenshot of Tails Greeter with persistence
Feature Branch: web/10630-persistence-instructions
Parent Task: #8590 (closed)
Original created by @sajolida on 10630 (Redmine)