Sessions: fixed logout() destroying normal session (instead of elevated) if $level = USER_LEVEL_CHPREF. Possible very minor security concern: elevated sessions were not fully destroyed, so if a normal session is opened from the same IP, the elevated one may be reusable for 15 minutes.
# Thanks to http://phaedo.cx/archives/2007/07/25/tools-for-optimizing-your-website-etag-and-expire-headers-in-django-apache-and-lighttpd/ for this.
FileETag MTime Size
# http://www.askapache.com/htaccess/apache-speed-expires.html
<IfModule mod_headers.c>
<FilesMatch "\.(jpg|jpeg|png|gif|js|css)$">
Header set Expires "Wed, 1 Jan 2020 20:00:00 GMT"
</FilesMatch>
</IfModule>
# http://www.askapache.com/htaccess/apache-speed-compression.html
<IfModule mod_deflate.c>
<FilesMatch "\.(js|css)$">
SetOutputFilter DEFLATE
</FilesMatch>
</IfModule>