Fixed broken link to distill-style blog post (alshedivat#957)

Updated README.md with the correct link to the distill-style blog post
example.

README.md

@@ -189,7 +189,7 @@ Now, feel free to customize the theme however you like (don't forget to change t
 > Note: this approach is only necessary if you would like to build an older or very custom version of al-folio.
 
 First, download the necessary modules and install them into a docker image called `al-folio:Dockerfile` (this command will build an image which is used to run your website afterwards. Note that you only need to do this step once. After you have the image, you no longer need to do this anymore):
-  
+
 
 ```bash
 $ ./bin/docker_build_image.sh  
@@ -408,7 +408,7 @@ If the entry matches one of the combinations of the last names and the first nam
 <details><summary>(click to expand) <strong>Buttons (through custom bibtex keywords):</strong></summary>
 
 There are several custom bibtex keywords that you can use to affect how the entries are displayed on the webpage:
-   
+
 - `abbr`: Adds an abbreviation to the left of the entry. You can add links to these by creating a venue.yaml-file in the _data folder and adding entries that match.
 - `abstract`: Adds an "Abs" button that expands a hidden text field when clicked to show the abstract text
 - `arxiv`: Adds a link to the Arxiv website (Note: only add the arxiv identifier here - the link is generated automatically)
@@ -421,9 +421,9 @@ There are several custom bibtex keywords that you can use to affect how the entr
 - `poster`: Adds a "Poster" button redirecting to a specified file (if a full link is not specified, the file will be assumed to be placed in the /assets/pdf/ directory)
 - `slides`: Adds a "Slides" button redirecting to a specified file (if a full link is not specified, the file will be assumed to be placed in the /assets/pdf/ directory)
 - `website`: Adds a "Website" button redirecting to the specified link
-   
+
 You can implement your own buttons by editing the bib.html file.
-   
+
 </details>
 
 ---
@@ -450,9 +450,9 @@ To do this, edit the collections in the `_config.yml` file, create a correspondi
 
 The theme allows you to create blog posts in the [distill.pub](https://distill.pub/) style:
 
-<p align="center"><a href="https://alshedivat.github.io/al-folio/blog/2018/distill/" target="_blank"><img src="https://raw.githubusercontent.com/alshedivat/al-folio/master/assets/img/distill-screenshot.png" width=700></a></p>
+<p align="center"><a href="https://alshedivat.github.io/al-folio/blog/2021/distill/" target="_blank"><img src="https://raw.githubusercontent.com/alshedivat/al-folio/master/assets/img/distill-screenshot.png" width=700></a></p>
 
-For more details on how to create distill-styled posts using `<d-*>` tags, please refer to [the example](https://alshedivat.github.io/al-folio/blog/2018/distill/).
+For more details on how to create distill-styled posts using `<d-*>` tags, please refer to [the example](https://alshedivat.github.io/al-folio/blog/2021/distill/).
 
 #### Full support for math & code
 
@@ -506,7 +506,7 @@ You may also use the following codes for displaying this in any other pages.
 
 #### Theming
 A variety of beautiful theme colors have been selected for you to choose from.
-The default is purple, but you can quickly change it by editing the 
+The default is purple, but you can quickly change it by editing the
 `--global-theme-color` variable in the `_sass/_themes.scss` file.
 Other color variables are listed there as well.
 The stock theme color options available can be found at `_sass/variables.scss`.
@@ -560,4 +560,3 @@ The theme is available as open source under the terms of the [MIT License](https
 
 Originally, **al-folio** was based on the [\*folio theme](https://github.com/bogoli/-folio) (published by [Lia Bogoev](https://liabogoev.com) and under the MIT license).
 Since then, it got a full re-write of the styles and many additional cool features.
-