Reorganize sidebar links

Favouring the official channels at the top of the list. Closeselixir-lang#587

Author: eksperimental

_includes/important-links.html

@@ -3,19 +3,19 @@ <h3 class="widget-title">Join the Community</h3>
 <ul>
 <li><aclass="spec" href="irc://irc.freenode.net/elixir-lang">#elixir-lang on freenode IRC</a></li>
 <li><aclass="spec" href="https://elixir-slackin.herokuapp.com/">Elixir on Slack</a></li>
-<li><aclass="spec" href="http://elixir.meetup.com">Elixir meetups around the world</a></li>
 <li><aclass="spec" href="https://groups.google.com/group/elixir-lang-talk">elixir-talk mailing list (questions)</a></li>
-<li><aclass="spec" href="https://groups.google.com/group/elixir-lang-core">elixir-core mailing list (development)</a></li>
-<li><aclass="spec" href="https://github.com/elixir-lang/elixir/issues">Issue tracker</a></li>
 <li><aclass="spec" href="https://twitter.com/elixirlang">@elixirlang on Twitter</a></li>
+<li><aclass="spec" href="http://elixir.meetup.com">Meetups around the world</a></li>
+<li><aclass="spec" href="https://github.com/elixir-lang/elixir/wiki">Wiki with events, resources and talks organized by the community</a></li>
 </ul>
 </div>
 
 <divclass="widget">
 <h3class="widget-title">Important links</h3>
 <ul>
 <li><aclass="spec" href="https://github.com/elixir-lang/elixir">Source Code</a></li>
-<li><aclass="spec" href="https://github.com/elixir-lang/elixir/wiki">Wiki with events, resources and talks organized by the community</a></li>
+<li><aclass="spec" href="https://github.com/elixir-lang/elixir/issues">Issue tracker</a></li>
+<li><aclass="spec" href="https://groups.google.com/group/elixir-lang-core">elixir-core mailing list (development)</a></li>
 <li><aclass="spec" href="/crash-course.html">Crash course for Erlang developers</a></li>
 </ul>
 </div>