DietPi-Software | Add shell selection with zsh and fish

[MichaIng]

Quite a significant number if Linux users use/like zsh, quite some fish. So related install options and a shell selection in dietpi-software would be nice, which installs the selected shell, adds an adapted DietPi login script and makes it the default shell for root and dietpi (as long as it exists) users.

[therealresonix]

@MichaIng Would be nice to have an update on this; Would be cool if you could add it to one of the next releases.

[oxoocoffee]

Any updates on this request?

[ndrew222]

I've drafted up a pull request #7452
Solution has been inspired by #5211