upstream: Update to raw code of jetpack v2.93
dev_unlinkwpcom:change class.jetpack.php and [slim]jetpack.php to unlink from wp.com
dev_unlinkwpcom:removed photon and devicepx
dev_unlinkwpcom:reload akismet menu while it's active
dev_unlinkwpcom:fix the hidden omnisearch menu bug
dev_rmlinkedmod:remove modules requiring connections to wp.com
dev_bettercsseditor:replace codemirror back with ace for better css hint support
develop: merge update branch of dev_unlinkwpcom
Merge branch 'dev_rmlinkedmod' into develop
Merge branch 'dev_bettercsseditor' into develop
dev_rmlinkedmod:remove holiday snow error message
Merge branch 'dev_rmlinkedmod' into develop
dev_unlinkwpcom: rebrand slimjetpack as slim jp in admin pages
Merge branch 'dev_unlinkwpcom' into develop
merge develop branch into release for Slim JP v2.93