Improve Account Setup Screen
- Explain what "account creation" means on first run (#151 (closed))
- Use hints instead of dedicated text views
- Move password strength meter up into the user's view
- Always move user's view to current input field
- Improve "Forgot Password" dialog
Please note that the dialog button colors will be changed in !214 (merged) to the official design. Here they have the old colors.
Closes #151 (closed), #207 (closed)