add: A new theme 'ys'.

themes/ys.zsh-theme

+# Clean, simple, compatible and meaningful.
+# Tested on Linux, Unix and Windows.
+# It is recommanded to use with a dark background and the font Inconsolata.
+# Colors: black, red, green, yellow, *blue, magenta, cyan, and white.
+#
+# Oct 2012 ys
+
+function box_name {
+    [ -f ~/.box-name ] && cat ~/.box-name || hostname -s
+}
+
+local current_dir='${PWD/#$HOME/~}'
+local git_info='$(git_prompt_info)'
+
+ZSH_THEME_GIT_PROMPT_PREFIX=" %{$fg[white]%}on%{$reset_color%} git:%{$fg[cyan]%}"
+ZSH_THEME_GIT_PROMPT_SUFFIX="%{$reset_color%}"
+ZSH_THEME_GIT_PROMPT_DIRTY=" %{$fg[red]%}x"
+ZSH_THEME_GIT_PROMPT_CLEAN=" %{$fg[green]%}o"
+
+PROMPT="
+# %{$fg[green]%}%n%{$reset_color%} %{$fg[white]%}at%{$reset_color%} %{$fg[cyan]%}$(box_name)%{$reset_color%} %{$fg[white]%}in%{$reset_color%} %{$terminfo[bold]$fg[yellow]%}${current_dir}%{$reset_color%}${git_info} %{$fg[white]%}[%*]%{$reset_color%}
+%{$fg[red]%}$ %{$reset_color%}"