[real-world uses] Rename writeLaTeX to Overleaf

Rename writeLaTeX to Overleaf in the list of real-world uses.

https://www.overleaf.com/blog/190-writelatex-is-continued-overleaf

Author: hubgit

doc/realworld.html

@@ -143,6 +143,7 @@ <h2>CodeMirror real-world uses</h2>
       <li><a href="http://www.greycampus.com/opencampus">OpenCampus</a></li>
       <li><a href="http://clrhome.org/asm/">ORG</a> (z80 assembly IDE)</li>
       <li><a href="https://github.com/mamacdon/orion-codemirror">Orion-CodeMirror integration</a> (running CodeMirror modes in Orion)</li>
+      <li><a href="https://www.overleaf.com/">Overleaf</a> (Collaborative LaTeX Editor)</li>
       <li><a href="http://paperjs.org/">Paper.js</a> (graphics scripting)</li>
       <li><a href="http://pharaoh.js.org/">Pharaoh</a> (browser &amp; desktop editor for the classroom)</li>
       <li><a href="http://prinbit.com/">PrinBit</a> (collaborative coding tool)</li>
@@ -196,7 +197,6 @@ <h2>CodeMirror real-world uses</h2>
       <li><a href="http://www.wescheme.org/">WeScheme</a> (learning tool)</li>
       <li><a href="https://github.com/b3log/wide">Wide</a> (golang web IDE)</li>
       <li><a href="http://wordpress.org/extend/plugins/codemirror-for-codeeditor/">WordPress plugin</a></li>
-      <li><a href="https://www.writelatex.com">writeLaTeX</a> (Collaborative LaTeX Editor)</li>
       <li><a href="http://www.xosystem.org/home/applications_websites/xosystem_website/xoside_EN.php">XOSide</a> (online editor)</li>
       <li><a href="http://videlibri.sourceforge.net/cgi-bin/xidelcgi">XQuery tester</a></li>
       <li><a href="http://q42jaap.github.io/xsd2codemirror/">xsd2codemirror</a> (convert XSD to CM XML completion info)</li>