Display status of error at right prompt side

Install/Templates/fish/functions/fish_right_prompt.fish

@@ -0,0 +1,10 @@
+function fish_right_prompt --description 'Write out the prompt on the right'
+	set -l last_status $status
+
+    if not test $last_status -eq 0
+        set_color $fish_color_error
+		echo $last_status
+    end
+
+    set_color normal
+end