docs: Add initial docs to groups and rbac (#4455)

* docs: Add initial docs to groups and rbac

* Update manifest

* Apply suggestions from code review

Co-authored-by: Joe Previte <jjprevite@gmail.com>

* use single user icon

* chore: add labels and standardize enterprise messaging

* clarify template role

* add groups role

* fix typo

* rename access to use

Co-authored-by: Joe Previte <jjprevite@gmail.com>
Co-authored-by: Ben <me@bpmct.net>

docs/admin/rbac.md

@@ -0,0 +1,18 @@
+# Role Based Access Control (RBAC)
+
+Use RBAC to define which users and [groups](./groups.md) can use specific templates in Coder.
+
+![rbac](../images/template-rbac.png)
+
+The "Everyone" group makes a template accessible to all users. This can be removed to make a template private.
+
+## Permissions
+
+You can set the following permissions:
+
+- **Admin**: Read, use, edit, push, and delete
+- **View**: Read, use
+
+## Enabling this feature
+
+This feature is only available with an enterprise license. [Learn more](./enterprise.md)