Add details to the documentation.

Add "or-show" to "project create" and "role create" in the documentation.

Closes-Bug: #1475485
Change-Id: I2d98766c4ddd8b2022012c4f6c5e1d4fcebfc42a

Author: heha

doc/source/command-objects/project.rst

@@ -18,6 +18,7 @@ Create new project
         [--description <description>]
         [--enable | --disable]
         [--property <key=value>]
+        [--or-show]
         <name>
 
 .. option:: --domain <domain>
@@ -49,6 +50,12 @@ Create new project
     Add a property to :ref:`\<name\> <project_create-name>`
     (repeat option to set multiple properties)
 
+.. option:: --or-show
+
+    Return existing project
+
+    If the project already exist return the existing project data and do not fail.
+
 .. _project_create-name:
 .. describe:: <name>
 

doc/source/command-objects/role.rst

@@ -71,8 +71,15 @@ Create new role
 .. code:: bash
 
     os role create
+        [--or-show]
         <name>
 
+.. option:: --or-show
+
+    Return existing role
+
+    If the role already exist return the existing role data and do not fail.
+
 .. describe:: <name>
 
     New role name