Add more useful websites to website page

Image compressing, and web-accessibility websites.

websites.html

@@ -44,6 +44,9 @@
 					<li><a href="https://coolors.co/generate" target="_blank" rel="noopener noreferrer ">coolors.co/generate</a></li>
 					<li><a href="https://webpagetest.org/" target="_blank" rel="noopener noreferrer ">webpagetest.org</a></li>
 					<li><a href="https://tools.pingdom.com/" target="_blank" rel="noopener noreferrer ">tools.pingdom.com</a></li>
+					<li><a href="https://vecta.io/nano" target="_blank" rel="noopener noreferrer">vecta.io/nano</a></li>
+					<li><a href="https://tinypng.com/" target="_blank" rel="noopener noreferrer">tinypng.com</a></li>
+					<li><a href="https://webaim.org/resources/contrastchecker/" target="_blank" rel="noopener noreferrer">webaim.org/resources/contrastchecker/</a></li>
 				</ul>
 			</section>