Added check for constant "WPSC_DISABLE_HTACCESS_UPDATE" to disable updating the .htaccess rules. Ref: http://wordpress.org/support/topic/cache-control-max-age3-must-revalidate?replies=1


git-svn-id: https://plugins.svn.wordpress.org/wp-super-cache/trunk@750280 b8457f37-d9ea-0310-8a92-e5e31aec5664