Add configuration for zsh

- Add ~/.zshrc
  + Configure on how the `history` works
  + Enable nicer `cd` and globbing behavior
  + Enable tab completion, and make them feel nicer
  + Enable VI mode and add some VI-like key bindings
- Add ~/.zlogout clearing the screen
- Add ~/.config/zsh/.zshrc and make it dispatch to ~/.zshrc
  to make `zsh` use the same configuration even on more
  recent Debian/Ubuntu machines that do not look for
  ~/.zshrc any more
- Ensure ~/.local/state/zsh/ exists

.profile

@@ -51,6 +51,10 @@ if [ -n "$BASH_VERSION" ] && [ -f "$HOME/.bashrc" ]; then
 fi
 
 
+# `zsh`-specific configurations are automatically sourced from ~/.zshrc,
+# which then also ensures that this file is sourced
+
+
 # Put local executables on the `$PATH`
 _prepend_to_path "$HOME/.local/bin"