add "fishy" theme to emulate Fish shell's prompt

themes/fishy.zsh-theme

+# ZSH Theme emulating the Fish shell's default prompt.
+
+local user_color='green'; [ $UID -eq 0 ] && user_color='red'
+PROMPT='%n@%m %{$fg[$user_color]%}%~%{$reset_color%}%(!.#.>) '
+PROMPT2='%{$fg[red]%}\ %{$reset_color%}'
+RPS1='%(?..%{$fg[red]%}%? ↵%{$reset_color%})$(git_prompt_info)'
+
+ZSH_THEME_GIT_PROMPT_PREFIX=" %{$fg[cyan]%}"
+ZSH_THEME_GIT_PROMPT_SUFFIX="%{$reset_color%}"