Numerous documentation and test code fixes for HTML Purifier loading

- Improve documentation for stub files
- Synchronize stub files between extras/ and library/
- Remove unnecessary include in function file
- Remove special treatment of Bootstrap
- Improve docs for HTMLPurifier, converted singleton to use static member variables and removed reference
- Add HTMLPurifier.path.php stub file
- Update sample test settings
- Reorganize includes in test files

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@1559 48356398-32a2-884e-a903-53898d9a118a

maintenance/generate-includes.php

@@ -22,7 +22,6 @@ $exclude_dirs = array(
 $exclude_files = array(
     'HTMLPurifier/Lexer/PEARSax3.php',
     'HTMLPurifier/Lexer/PH5P.php',
-    'HTMLPurifier/Bootstrap.php',
 );
 
 // Determine what files need to be included:
@@ -140,9 +139,6 @@ $php = "<?php
  *      library directory; this is not auto-set.
  */
 
-// Treat this file specially, as it is detached from the rest of the library
-require_once 'HTMLPurifier/Bootstrap.php';
-
 ";
 
 foreach ($files as $file) {