update setup help link to go directly to the docs for the current version, not...

update setup help link to go directly to the docs for the current version, not just the latest docs in general.

frontend/app/setup/components/Setup.react.js

 import React, { Component, PropTypes } from "react";
 
 import LogoIcon from 'metabase/components/LogoIcon.react';
+import MetabaseSettings from "metabase/lib/settings";
+
 import UserStep from './UserStep.react';
 import DatabaseStep from './DatabaseStep.react';
 import PreferencesStep from './PreferencesStep.react';
@@ -20,9 +22,10 @@ export default class Setup extends Component {
     }
 
     renderFooter() {
+        const { tag } = MetabaseSettings.get('version');
         return (
             <div className="SetupHelp bordered border-dashed p2 rounded mb4" >
-                If you feel stuck, <a className="link" href="http://www.metabase.com/docs/latest/getting-started">our getting started guide</a> is just a click away.
+                If you feel stuck, <a className="link" href={"http://www.metabase.com/docs/"+tag+"/getting-started/start.html"} target="_blank">our getting started guide</a> is just a click away.
             </div>
         );
     }