Fix consistency in menus and pages

In some pages at the top it had 'and' but in the menu it had instead a
'&'. The menus (JavaScript and otherwise) now has 'and' to match the
pages. The file nojs-menu.html has been checked for broken links and
indeed one at least was fixed. Very few top level html files need to be
checked now. Some that are entirely generated should be okay but links
will still be checked to be sure.

Some cases of '(Mis)features' from the previous commit were also
corrected to '(mis)features' as this is also part of menu and page
consistency.

The files markdown.{md,html} have had the menus updated too but there
are some other changes that were works in progress. This file is not
thus completed but will be sometime soon.

bugs.html

@@ -80,7 +80,7 @@
 
             <div class="outfit-font">
               <a href="./bugs.html" class="sub-item-link">
-                Bugs &amp; (Mis)features
+                Bugs and (mis)features
               </a>
             </div>
           </div>
@@ -106,7 +106,7 @@
 
             <div class="outfit-font">
               <a href="./next/index.html" class="sub-item-link">
-                Rules &amp; Guidelines
+                Rules and Guidelines
               </a>
             </div>
           </div>
@@ -236,7 +236,7 @@
             </a>
 
             <a class="mobile-submenu-item" href="./bugs.html">
-              Bugs &amp; (Mis)features
+              Bugs and (mis)features
             </a>
 
           </div>
@@ -254,7 +254,7 @@
             </a>
 
             <a class="mobile-submenu-item" href="./next/index.html">
-              Rules &amp; Guidelines
+              Rules and Guidelines
             </a>
 
             <a class="mobile-submenu-item" href="./news.html">