Update default local URL (#120)

Merge pull request 120

Author: DirtyF

README.md

@@ -2,6 +2,8 @@
 
 *Minima is a one-size-fits-all Jekyll theme for writers*. It's Jekyll's default (and first) theme. It's what you get when you run `jekyll new`.
 
+[Theme preview](https://jekyll.github.io/minima/)
+
 ![minima theme preview](/screenshot.png)
 
 ## Installation
@@ -138,7 +140,7 @@ Bug reports and pull requests are welcome on GitHub at https://github.com/jekyll
 
 To set up your environment to develop this theme, run `bundle install`.
 
-To test your theme, run `bundle exec rake preview` and open your browser at `http://localhost:4000/minima/`. This starts a Jekyll server using your theme and the contents. As you make modifications, your site will regenerate and you should see the changes in the browser after a refresh.
+To test your theme, run `bundle exec rake preview` and open your browser at `http://localhost:4000`. This starts a Jekyll server using your theme and the contents. As you make modifications, your site will regenerate and you should see the changes in the browser after a refresh.
 
 ## License