Added the descrition of evolution engines in eoEngine

and links to SGAI STL Web site in eoTutorial and eoProgramming

eo/tutorial/html/eoTutorial.html

@@ -11,8 +11,9 @@
 documentation</a></font></font></b>
 <hr WIDTH="100%">
 <center><b><font color="#FF0000">Welcome to EO, the Evolving Objects library,
-and to</font></b>
-<b><font color="#FF0000"></font></b>&nbsp;
+and to</font></b></center>
+
+<center>
 <h1>
 <font color="#FF0000">EO Tutorial</font></h1></center>
 
@@ -63,6 +64,12 @@ and to quickly reach some specific part of the code.</li>
 
 <br>The top page of each class documentation is for instance the inheritance
 diagram of the class, and you'll learn a lot by simply looking at it.
+<li>
+For those who wish to get deeper in STL (Standard Template Library), you
+might visit the well documented <a href="http://www.sgi.com/Technology/STL/">SGI
+STL Web site</a>. But don't forget you'll find the very basic minimum in
+EO <a href="eoProgramming.html#STL">programming hints</a>.</li>
+
 <li>
 And, last but not least, we assume you know approximately that an Evolutionary
 Algorithm looks like this, but otherwise you can try this <a href="eoIntroEA.html">very