Modernize RPM info docs (#4331)

* Modernize RPMinfo XML

* Improve RPM constant page grouping

Remove useless para tag and fix indentation

Author: Girgias

reference/rpminfo/book.xml

@@ -1,29 +1,27 @@
 <?xml version="1.0" encoding="utf-8"?>
 <!-- $Revision$ -->
-
 <book xml:id="book.rpminfo" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
  <?phpdoc extension-membership="pecl" ?>
  <title>RpmInfo</title>
  <titleabbrev>RpmInfo</titleabbrev>
 
  <preface xml:id="intro.rpminfo">
   &reftitle.intro;
-  <para>
+  <simpara>
    This extension enables you to retrieve information from RPM files
    or from the installed RPMs database.
-  </para>
-  <para>
+  </simpara>
+  <simpara>
    It also provides a <literal>rpm</literal> stream wrapper to retrieve RPM content
    (since version 1.0.0 with librpm  &gt;=  4.13).
-  </para>
+  </simpara>
  </preface>
 
  &reference.rpminfo.setup;
  &reference.rpminfo.constants;
  &reference.rpminfo.reference;
 
 </book>
-
 <!-- Keep this comment at the end of the file
 Local variables:
 mode: sgml