Problem: User data input is confusing
See user feedback:
https://gitlab.com/exosphere/exosphere/wikis/user-testing/person-a
- "The most confusing thing was the SSH key and the boot script"
- "Something I don't need should be hidden, until I want it, then it should be in a place I can easily find"
Solution: Hide the user data by default
Fixes #126 (closed)