Update README.md

The original link seems to be dead, reverting to wayback machine

README.md

@@ -1214,7 +1214,7 @@ CyberTalks</b></a> - talks, interviews, and article about cybersecurity.<br>
 ##### :black_small_square: A piece of history
 
 <p>
-&nbsp;&nbsp;:small_orange_diamond: <a href="http://ftp.arl.army.mil/~mike/howto/"><b>How to Do Things at ARL</b></a> - how to configure modems, scan images, record CD-ROMs, and other.<b>*</b><br>
+&nbsp;&nbsp;:small_orange_diamond: <a href="http://web.archive.org/web/20190221103734/https://ftp.arl.army.mil/~mike/howto/"><b>How to Do Things at ARL</b></a> - how to configure modems, scan images, record CD-ROMs, and other.<b>*</b><br>
 </p>
 
 ##### :black_small_square: Other