Updated architecture diagram in docs

* Sahara component now is colored like others integrated components
* Removed Cluster Configuration Manager as unrelated part of Sahara
* Added more services which Sahara can connect to (Heat, Cinder)
* Replaced Deployment Engine with Vendor Plugins
* Added EDP block
* Updated appropriate bullet points

Change-Id: I77a3a3fd92a0dc7ffa1eeb24a3cdeddd4c6c6798
(cherry picked from commit e681d1167ceb2878b4ccd95ea4ef3f0758c2e774)