Add details and clarify examples on casing

This change adds some more detail to the roles section of the
casing documentation for keystone, as well as clarifying the
examples given for users and projects. Also added project tags
casing.

Change-Id: I55447c8b599ab48021bd95204c4bf3c5bc7e690c

doc/source/admin/identity-case-insensitive.rst

@@ -25,7 +25,15 @@ which creates a new user by the name of "myuser" will return a
 
 .. code-block:: console
 
-    POST /v3/users {name: myuser}
+    POST /v3/users
+
+.. code-block:: json
+
+    {
+        "user": {
+            "name": "myuser"
+        }
+    }
 
 Projects
 --------
@@ -36,7 +44,22 @@ which creates a new project by the name of "foobar" will return a
 
 .. code-block:: console
 
-    POST /v3/projects {name: foobar}
+    POST /v3/projects
+
+.. code-block:: json
+
+    {
+        "project": {
+            "name": "foobar"
+        }
+    }
+
+Project Tags
+^^^^^^^^^^^^
+
+While project names are case-insensitive, project tags are case-sensitive.
+A tag with the value of ``mytag`` is different than ``MyTag``, and both values
+can be stored in the same project.
 
 Roles
 -----
@@ -47,6 +70,14 @@ roles, it creates "admin", "member", and "reader". If another role, "Member"
 since it considers the name "Member" equivalent to "member". Note that case
 is preserved in this event.
 
+.. note::
+  As of the Rocky release, keystone will create three default roles when
+  `keystone-manage bootstrap` is run: (``admin``, ``member``, ``reader``). For
+  existing deployments, this can cause issues if an existing role matches one
+  of these roles. Even if the casing is not an exact match
+  (``member`` vs ``Member``), it will report an error since roles are
+  considered case-insensitive.
+
 Backends
 ========