Updates to CleverCMS, Cm_Redis, other extensions

* Fix installation issues with CleverCMS extension.
* Updates to Cm_Redis.
* Updates to Netzarbeiter_CustomerActivation.
* Add generic dispatch events to Aoe_Scheduler Observer model.
* Updates to Fontis_Blog.
Extensions split out into Composer dependencies

Extensions are no longer included in the main Mercator repository. Each
extension has its own separate repository, and extensions are installed using
Composer.
Merge 1.8.1.0 upstream release