Sync the translation of "Part I - Introduction"

prologue/organization.xml

@@ -14,7 +14,7 @@
   <para>本书被分为以下三个部分。</para>
 
   <sect2>
-    <title>第一部分 - 介绍</title>
+    <title>第一部分 - 引言</title>
 
     <!--para>Part I explains a few important notes on how to proceed with the
     LFS installation.  This section also provides meta-information about