Use Control Plane instead of Master (#18438)

* Use Control Plane instead of Master

* improve image. The SVG was not matching the PNG, so I basically had to re-create it from scratch. I kept the visual similarities as mush as possible

* remove tautological phrase

* fix glossary references as well

* improve cluster glossary to move from Master to Control Plane

* improve english form

content/en/docs/reference/glossary/kube-controller-manager.md

@@ -4,14 +4,14 @@ id: kube-controller-manager
 date: 2018-04-12
 full_link: /docs/reference/command-line-tools-reference/kube-controller-manager/
 short_description: >
-  Component on the master that runs controllers.
+  Control Plane component that runs controller processes.
 
 aka: 
 tags:
 - architecture
 - fundamental
 ---
- Component on the master that runs {{< glossary_tooltip text="controllers" term_id="controller" >}}.
+ Control Plane component that runs {{< glossary_tooltip text="controller" term_id="controller" >}} processes.
 
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