[wwwdocs,Ada] Fix four links and adjust one in readings.html

[Gerald Pfeifer]

This updates five Ada-related links, four borken ones to adaic.org
and the libre.adacore.com that redirects now.

Applied.

Gerald

Index: readings.html
===================================================================
RCS file: /cvs/gcc/wwwdocs/htdocs/readings.html,v
retrieving revision 1.228
diff -u -3 -p -r1.228 readings.html
--- readings.html       31 Mar 2013 15:37:44 -0000      1.228
+++ readings.html       31 Mar 2013 17:06:51 -0000
@@ -551,11 +551,11 @@ Intel®64 and IA-32 Architectures Sof
        Reference Manual</a></li>
      <li><a 
href="http://www.adaic.org/resources/add_content/standards/05rat/html/Rat-TTL.html";>Ada&nbsp;2005
        Rationale</a></li>
-     <li><a href="http://www.adaic.com/standards/95aarm/html/AA-TTL.html";>
+     <li><a 
href="http://www.adaic.org/resources/add_content/standards/95aarm/AARM_HTML/AA-TTL.html";>
      Annotated Ada&nbsp;95 Reference Manual</a></li>
-     <li><a href="http://www.adaic.com/standards/95lrm/html/RM-TTL.html";>
+     <li><a 
href="http://www.adaic.org/resources/add_content/standards/95lrm/ARM_HTML/RM-TTL.html";>
      Ada&nbsp;95 Reference Manual</a></li>
-     <li><a 
href="http://www.adaic.com/standards/95rat/RAThtml/rat95-copyright.html";>
+     <li><a 
href="http://www.adaic.org/resources/add_content/standards/95rat/rat95html/rat95-contents.html";>
      Ada&nbsp;95 Rationale</a></li>
      <li><a href="http://archive.adaic.com/standards/83lrm/html/ada_lrm.html";>
      Ada&nbsp;83 Reference Manual</a></li>
@@ -578,10 +578,10 @@ Intel&reg;64 and IA-32 Architectures Sof
 
  <li>Other resources:
  <ul>
-   <li><a href="http://libre.adacore.com/libre/";>AdaCore &mdash; Libre 
Site</a></li>
+   <li><a href="http://libre.adacore.com/";>AdaCore &mdash; Libre Site</a></li>
    <li><a href="https://www2.adacore.com/gap-static/GNAT_Book/html/";>GNAT:
    The GNU Ada Compiler</a></li>
-   <li><a href="http://www.adaic.org/docs/95style/html/cover.html";>Ada
+   <li><a 
href="http://www.adaic.org/resources/add_content/docs/95style/html/cover.html";>Ada
    Quality &amp; Style Guide</a></li>
    <li><a 
href="http://www.sigada.org/ada_letters/jun2004/ravenscar_article.pdf";>Guide
    for the use of the Ada Ravenscar Profile in high integrity