update to 2.9.3

git-svn-id: https://plugins.svn.wordpress.org/jetpack-widget-visibility/trunk@892213 b8457f37-d9ea-0310-8a92-e5e31aec5664
Merge branch 'master' of git://github.com/wp-plugins/jetpack-widget-visibility into lechnology

Conflicts:
	widget-visibility/widget-conditions.php