update Mastodon formatting

Author: jmckenna

_templates/indexsidebar.html

@@ -8,7 +8,7 @@ <h3>Navigation</h3>
 <a href="{{ pathto('documentation') }}" title="Documentation">Documentation</a><br>
 <a href="{{ pathto('faq') }}" title="FAQ">FAQ</a><br>
 <a href="{{ pathto('psc') }}" title="PSC">PSC</a><br>
-<a href="https://mastodon.social/@mapserver@fosstodon.org" title="Mastodon" target="_blank">Masstodon</a>
+<a href="https://fosstodon.org/@mapserver" title="Mastodon" target="_blank">Mastodon</a>
 </p>
 <a href="https://www.osgeo.org/" target="_blank">
     <img src="{{ pathto("_static/OSGeo_project.png", 1) }}" alt="OSGeo" border="0px; text-decoration:none" />

_templates/layout.html

@@ -19,7 +19,7 @@ <h4 class="ribbon">DOCS PREVIEW</h4>
       <a href="https://github.com/mapserver/mapserver/issues/" title="Issue Tracker (MapServer core)">Issue Tracker</a> |
       <a href="{{ pathto('community/service_providers') }}" title="Professional Service Providers">Service Providers</a> |      
       <a href="{{ pathto('faq') }}" title="Frequently Asked Questions">FAQ</a> |
-      <a href="https://mastodon.social/@mapserver@fosstodon.org" title="Mastodon" target="_blank">Masstodon</a> |
+      <a href="https://fosstodon.org/@mapserver" title="Mastodon" target="_blank">Mastodon</a> |
       <a href="{{ pathto('download') }}" title="Download Source or Binaries">Download </a> |
       <a class="badge" href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=KRJ2X44N3HA6U&source=url" target="_blank">
         <img src="https://img.shields.io/badge/donate-%E2%9D%A4%C2%A0-ff69b4.svg?style=flat" alt="Donate to MapServer">

_templates/sidebar2.html

@@ -8,5 +8,5 @@ <h3>Navigation</h3>
 <a href="{{ pathto('documentation') }}" title="Documentation">Documentation</a><br>
 <a href="{{ pathto('faq') }}" title="FAQ">FAQ</a><br>
 <a href="{{ pathto('psc') }}" title="PSC">PSC</a><br>
-<a href="https://mastodon.social/@mapserver@fosstodon.org" title="Mastodon">https://mastodon.social/@mapserver@fosstodon.org</a>
+<a href="https://fosstodon.org/@mapserver" title="Mastodon">Mastodon</a>
 </p>

en/index.txt

@@ -26,7 +26,7 @@ lists, etc.
    :alt: Digital Object Identifier (DOI) for MapServer
 
 .. tip::
-    Follow MapServer on `Fosstodon <https://fosstodon.org/@mapserver@fosstodon.org>`__
+    Follow MapServer on `Fosstodon <https://fosstodon.org/@mapserver>`__
 
 :ref:`More about MapServer <about>`