[3.1.0] The bulk of autoload support added

- Add FSTools:globr()
- require_once removed from all files
- HTMLPurifier.autoload.php added to register autoload handler
- Removed redundant chdir in maintenance script
- Modified standalone to use HTMLPurifier.includes.php for including stuff
- Added maintenance script remove-require-once.php which we used once and should never use again

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@1516 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/Lexer/DOMLex.php

@@ -1,8 +1,5 @@
 <?php
 
-require_once 'HTMLPurifier/Lexer.php';
-require_once 'HTMLPurifier/TokenFactory.php';
-
 /**
  * Parser that uses PHP 5's DOM extension (part of the core).
  * 

library/HTMLPurifier/Lexer/DirectLex.php

@@ -1,7 +1,5 @@
 <?php
 
-require_once 'HTMLPurifier/Lexer.php';
-
 HTMLPurifier_ConfigSchema::define(
     'Core', 'DirectLexLineNumberSyncInterval', 0, 'int', '
 <p>

library/HTMLPurifier/Lexer/PEARSax3.php

@@ -1,8 +1,5 @@
 <?php
 
-require_once 'XML/HTMLSax3.php'; // PEAR
-require_once 'HTMLPurifier/Lexer.php';
-
 /**
  * Proof-of-concept lexer that uses the PEAR package XML_HTMLSax3 to parse HTML.
  * 

library/HTMLPurifier/Lexer/PH5P.php

@@ -1,7 +1,5 @@
 <?php
 
-require_once 'HTMLPurifier/Lexer/DOMLex.php';
-
 /**
  * Experimental HTML5-based parser using Jeroen van der Meer's PH5P library.
  * Requires PHP5, and occupies space in the HTML5 pseudo-namespace (may