markdown : remove the left spaces in the beginning of lines as it is not necessary. Not use ltrim to conserve the indent in the codes

git-svn-id: https://svn.fournier38.fr/svn/ProgSVN/trunk@1484 bf3deb0d-5f1a-0410-827f-c0cc1f45334c

markdown.php

@@ -329,7 +329,7 @@ class markdown
       }
 
       $this->debugMKD ("$lineTxt");
-      $res .= "$lineTxt\n";
+      $res .= substr ($lineTxt, end ($indentStack))."\n";
     }
 
     $this->debugMKD ("DEB1 : End of loop");