add a button to change from password to publickey access

[Mannshoch]

add a button that try to switch from password driven access to password-less access.

Idea:

1. create a new key
2. use the ssh password to setup the new key password
3. copy-id to server
4. try to connect with key -> change the authmethod if it work
5. If not working or errors appear -> remove the created key, log this information and further use password access.