Add Jetpack to mobile FAQ.

git-svn-id: https://plugins.svn.wordpress.org/wp-super-cache/trunk@1005136 b8457f37-d9ea-0310-8a92-e5e31aec5664
Catch up to SVN

git-svn-id: https://plugins.svn.wordpress.org/wp-super-cache/trunk@1005137 b8457f37-d9ea-0310-8a92-e5e31aec5664
Removing variable checks since wp_cache_debug does it already. Ref: https://github.com/Automattic/wp-super-cache/pull/15

git-svn-id: https://plugins.svn.wordpress.org/wp-super-cache/trunk@1005138 b8457f37-d9ea-0310-8a92-e5e31aec5664