small documentation errors

Hi!

1.
 From http://smarty.php.net/ :
	You can make your debug console persist by using SMARTY_DEBUG=1 or SMARTY_DEBUG=0 in the URL

In code there are checks for '=on' and '=off' (Smarty.class.php lines 1117,1121)
In 2.6.0 documentation (chapter 10) new possibility (of course) is not noted.

2. In downloaded docs chapter "Methods" is numbered like part, not a chapter ('I' instead of '13')

3. On a page 'Controlling Cacheability of Plugins' first example block is not properly closed in SGML.

WBR,
Konstantin