[wwwdocs] Colorize gcc-4.9/changes.html again

[Gerald Pfeifer]

Use global CSS classes instead of local styles (which browsers now
often block based on the server settings of gcc.gnu.org).

Committed.

Gerald

Index: gcc-4.9/changes.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/gcc-4.9/changes.html,v
retrieving revision 1.87
diff -u -r1.87 changes.html
--- gcc-4.9/changes.html        28 Jun 2015 15:19:47 -0000      1.87
+++ gcc-4.9/changes.html        20 Jan 2016 18:50:58 -0000
@@ -163,17 +163,17 @@
     <pre>
     $ g++ -fdiagnostics-color=always -S -Wall test.C
     <b>test.C:</b> In function &lsquo;<b>int foo()</b>&rsquo;:
-    <b>test.C:1:14:</b> <b style='color:magenta'>warning:</b> no return 
statement in function returning non-void [-Wreturn-type]
+    <b>test.C:1:14:</b> <span class="boldmagenta">warning:</span> no return 
statement in function returning non-void [-Wreturn-type]
      int foo () { }
-                  <b style='color:lime'>^</b>
-    <b>test.C:2:46:</b> <b style='color:red'>error:</b> template instantiation 
depth exceeds maximum of 900 (use -ftemplate-depth= to increase the maximum) 
instantiating &lsquo;<b>struct X&lt;100&gt;</b>&rsquo;
+                  <span class="boldlime">^</span>
+    <b>test.C:2:46:</b> <span class="boldred">error:</span> template 
instantiation depth exceeds maximum of 900 (use -ftemplate-depth= to increase 
the maximum) instantiating &lsquo;<b>struct X&lt;100&gt;</b>&rsquo;
      template &lt;int N&gt; struct X { static const int value = 
X&lt;N-1&gt;::value; }; template struct X&lt;1000&gt;;
-                                                  <b style='color:lime'>^</b>
+                                                  <span 
class="boldlime">^</span>
     <b>test.C:2:46:</b>   recursively required from &lsquo;<b>const int 
X&lt;999&gt;::value</b>&rsquo;
     <b>test.C:2:46:</b>   required from &lsquo;<b>const int 
X&lt;1000&gt;::value</b>&rsquo;
     <b>test.C:2:88:</b>   required from here
 
-    <b>test.C:2:46:</b> <b style='color:red'>error:</b> incomplete type 
&lsquo;<b>X&lt;100&gt;</b>&rsquo; used in nested name specifier
+    <b>test.C:2:46:</b> <span class="boldred">error:</span> incomplete type 
&lsquo;<b>X&lt;100&gt;</b>&rsquo; used in nested name specifier
     </pre></li>
 
     <li>With the new <a