Fixed typo in 'libraries'

about.html

@@ -5,7 +5,7 @@
 
 <p>See full history on <a href="https://github.com/seblucas">Github</a> to check all authors.</p>
 
-<p>COPS use some external libriries, check README for the details.</p>
+<p>COPS use some external libraries, check README for the details.</p>
 <h2>Copyright</h2>
 <p>This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License version 2 as published by the Free Software Foundation.</p>