[3.1.0] multitest.php now works again for all version, however, some hacks to PHPT are required

- Bootstrap hotfix to prevent multiple loading in standalone. We need a better way of doing this!
- Make extras/ autoloader polite too
- Initialize autoloaders in common.php
- Add trailing dash to "skip" in phpt
- Upgrade SimpleTest.php not to allow directories

git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@1554 48356398-32a2-884e-a903-53898d9a118a

library/HTMLPurifier/Bootstrap.php

@@ -20,6 +20,9 @@ if (!defined('PHP_EOL')) {
     }
 }
 
+// :TODO: Might be slow
+if (!class_exists('HTMLPurifier_Bootstrap', false)) {
+
 /**
  * Bootstrap class that contains meta-functionality for HTML Purifier such as
  * the autoload function.
@@ -56,3 +59,6 @@ class HTMLPurifier_Bootstrap
     }
     
 }
+
+}
+