use 'required' instead of 'optional' for parameters

In swagger the attribute for required/optional is 'required', so we've
decided that's a better way to specify our parameters. This changes
the sphinx parser to use that when inserting (optional) into the
table.

We also make all 'path' parameters required, because we never specify
them in a table where they are not. I think them all being required:
false was an artifact of the data processing.

Part of bp:api-ref-in-rst

Change-Id: Ie2d012741d69430546fe1b10c9f16c853acb926a

api-ref/ext/rest_parameters.py

@@ -224,7 +224,7 @@ class RestParametersDirective(Table):
                     classes.append(min_ver_css_name)
                 trow = nodes.row(classes=classes)
                 name = key
-                if values.get('optional') is True:
+                if values.get('required', False) is False:
                     name += " (Optional)"
                 trow += self.add_col(name)
                 trow += self.add_col(values.get('in'))

api-ref/source/parameters.yaml

@@ -20,217 +20,217 @@ admin_tenant_id:
   description: |
     The UUID of the administrative tenant.
   in: path
-  required: false
+  required: true
   type: string
 agent_build_id:
   description: |
     The UUID of the agent build.
   in: path
-  required: false
+  required: true
   type: string
 aggregate_id:
   description: |
     The aggregate ID.
   in: path
-  required: false
+  required: true
   type: string
 alias_1:
   description: |
     An alias for the extension name. For example, ``os-server-external-events``.
   in: path
-  required: false
+  required: true
   type: string
 attachment_id:
   description: |
     The UUID of the attachment.
   in: path
-  required: false
+  required: true
   type: string
 cell_id:
   description: |
     The UUID of the cell.
   in: path
-  required: false
+  required: true
   type: string
 certificate_id:
   description: |
     The certificate ID, as a string. The only valid value is ``root``.
   in: path
-  required: false
+  required: true
   type: string
 class_id:
   description: |
     The UUID of the quota class.
   in: path
-  required: false
+  required: true
   type: string
 console_id:
   description: |
     The UUID of the console.
   in: path
-  required: false
+  required: true
   type: string
 domain:
   description: |
     The registered DNS domain that the DNS drivers publish.
   in: path
-  required: false
+  required: true
   type: string
 fixed_ip_1:
   description: |
     The fixed IP of interest to you.
   in: path
-  required: false
+  required: true
   type: string
 flavor_extra_spec_key:
   description: |
     The extra spec key for the flavor.
   in: path
-  required: false
+  required: true
   type: string
 flavor_id:
   description: |
     The ID of the flavor.
   in: path
-  required: false
+  required: true
   type: string
 floating_ip_id:
   description: |
     The ID of the floating IP address.
   in: path
-  required: false
+  required: true
   type: string
 host_name:
   description: |
     The name of the host.
   in: path
-  required: false
+  required: true
   type: string
 hypervisor_id:
   description: |
     The UUID of the hypervisor.
   in: path
-  required: false
+  required: true
   type: string
 image_id:
   description: |
     The UUID of the image.
   in: path
-  required: false
+  required: true
   type: string
 instance_id:
   description: |
     The UUID of the instance.
   in: path
-  required: false
+  required: true
   type: string
 ip:
   description: |
     The IP address.
   in: path
-  required: false
+  required: true
   type: string
 key:
   description: |
     The metadata item key, as a string. Maximum length is 255 characters.
   in: path
-  required: false
+  required: true
   type: string
 keypair_name:
   description: |
     The keypair name.
   in: path
-  required: false
+  required: true
   type: string
 name_1:
   description: |
     The name of the DNS entry.
   in: path
-  required: false
+  required: true
   type: string
 network_id:
   description: |
     The UUID of the network.
   in: path
-  required: false
+  required: true
   type: string
 network_label:
   description: |
     The network label, such as ``public`` or ``private``.
   in: path
-  required: false
+  required: true
   type: string
 node_id:
   description: |
     The node ID.
   in: path
-  required: false
+  required: true
   type: string
 port_id_1:
   description: |
     The UUID of the port.
   in: path
-  required: false
+  required: true
   type: string
 request_id:
   description: |
     The ID of the request.
   in: path
-  required: false
+  required: true
   type: string
 security_group_default_rule_id:
   description: |
     The UUID of the security group rule.
   in: path
-  required: false
+  required: true
   type: string
 security_group_id:
   description: |
     The ID of the security group.
   in: path
-  required: false
+  required: true
   type: string
 security_group_rule_id:
   description: |
     The ID of the security group rule.
   in: path
-  required: false
+  required: true
   type: string
 server_group_id:
   description: |
     The UUID of the server group.
   in: path
-  required: false
+  required: true
   type: string
 server_id:
   description: |
     The UUID of the server.
   in: path
-  required: false
+  required: true
   type: string
 snapshot_id_2:
   description: |
     The UUID of the snapshot.
   in: path
-  required: false
+  required: true
   type: string
 tenant_id:
   description: |
     The UUID of the tenant in a multi-tenancy cloud.
   in: path
-  required: false
+  required: true
   type: string
 volume_id_1:
   description: |
     The unique ID for a volume.
   in: path
-  required: false
+  required: true
   type: string
 volume_type_id:
   description: |
     The unique ID for a volume type.
   in: path
-  required: false
+  required: true
   type: string
 
 # variables in query