Update INSTALL to avoid missing config snafu, update usage.xml.

Signed-off-by: Edward Z. Yang <ezyang@mit.edu>

INSTALL

@@ -331,11 +331,6 @@ Or move the cache directory somewhere else (no trailing slash):
 
 The interface is mind-numbingly simple:
 
-    $purifier = new HTMLPurifier();
-    $clean_html = $purifier->purify( $dirty_html );
-
-...or, if you're using the configuration object:
-
     $purifier = new HTMLPurifier($config);
     $clean_html = $purifier->purify( $dirty_html );
 
@@ -354,7 +349,8 @@ If your website is in UTF-8 and XHTML Transitional, use this code:
 <?php
     require_once '/path/to/htmlpurifier/library/HTMLPurifier.auto.php';
 
-    $purifier = new HTMLPurifier();
+    $config = HTMLPurifier_Config::createDefault();
+    $purifier = new HTMLPurifier($config);
     $clean_html = $purifier->purify($dirty_html);
 ?>
 

configdoc/usage.xml

@@ -260,7 +260,7 @@
    <line>64</line>
   </file>
   <file name="HTMLPurifier/URIScheme.php">
-   <line>75</line>
+   <line>81</line>
   </file>
  </directive>
  <directive id="URI.Base">