Add available params in ports client's comment

Some interfaces in ports client have **kwargs parameter, but no api
reference links are given. so this is to add "Available params" in their
comments.

Change-Id: I654f1e9872980c9ebaef772bf0340c953df666af
diff --git a/tempest/lib/services/network/ports_client.py b/tempest/lib/services/network/ports_client.py
old mode 100644
new mode 100755
index eba11d3..71f1103
--- a/tempest/lib/services/network/ports_client.py
+++ b/tempest/lib/services/network/ports_client.py
@@ -17,24 +17,49 @@
 class PortsClient(base.BaseNetworkClient):
 
     def create_port(self, **kwargs):
+        """Creates a port on a network.
+
+        Available params: see http://developer.openstack.org/
+                              api-ref-networking-v2.html#createPort
+        """
         uri = '/ports'
         post_data = {'port': kwargs}
         return self.create_resource(uri, post_data)
 
     def update_port(self, port_id, **kwargs):
+        """Updates a port.
+
+        Available params: see http://developer.openstack.org/
+                              api-ref-networking-v2.html#updatePort
+        """
         uri = '/ports/%s' % port_id
         post_data = {'port': kwargs}
         return self.update_resource(uri, post_data)
 
     def show_port(self, port_id, **fields):
+        """Shows details for a port.
+
+        Available params: see http://developer.openstack.org/
+                              api-ref-networking-v2.html#showPort
+        """
         uri = '/ports/%s' % port_id
         return self.show_resource(uri, **fields)
 
     def delete_port(self, port_id):
+        """Deletes a port.
+
+        Available params: see http://developer.openstack.org/
+                              api-ref-networking-v2.html#removePort
+        """
         uri = '/ports/%s' % port_id
         return self.delete_resource(uri)
 
     def list_ports(self, **filters):
+        """Lists ports to which the tenant has access.
+
+        Available params: see http://developer.openstack.org/
+                              api-ref-networking-v2.html#listPorts
+        """
         uri = '/ports'
         return self.list_resources(uri, **filters)