Apply a naming rule of GET to compute clients(l*)

[GET /resources] methods should be "list_<resource name>s"
or "show_<resource name>", so this patch applies the rule
to compute clients which name is "limits".

Partially implements blueprint consistent-service-method-names

Change-Id: Ibe30d01057936cea68f38984064dff107cdcbe5c
diff --git a/tempest/api/compute/limits/test_absolute_limits.py b/tempest/api/compute/limits/test_absolute_limits.py
index 974814c..06a77cc 100644
--- a/tempest/api/compute/limits/test_absolute_limits.py
+++ b/tempest/api/compute/limits/test_absolute_limits.py
@@ -27,7 +27,7 @@
     @test.idempotent_id('b54c66af-6ab6-4cf0-a9e5-a0cb58d75e0b')
     def test_absLimits_get(self):
         # To check if all limits are present in the response
-        absolute_limits = self.client.get_absolute_limits()
+        absolute_limits = self.client.show_limits()
         expected_elements = ['maxImageMeta', 'maxPersonality',
                              'maxPersonalitySize',
                              'maxServerMeta', 'maxTotalCores',
diff --git a/tempest/cmd/cleanup_service.py b/tempest/cmd/cleanup_service.py
index eb6f143..4dc03f9 100644
--- a/tempest/cmd/cleanup_service.py
+++ b/tempest/cmd/cleanup_service.py
@@ -377,7 +377,7 @@
 
     def dry_run(self):
         client = self.limits_client
-        quotas = client.get_absolute_limits()
+        quotas = client.show_limits()
         self.data['compute_quotas'] = quotas
 
 
diff --git a/tempest/services/compute/json/limits_client.py b/tempest/services/compute/json/limits_client.py
index d2aaec6..347467d 100644
--- a/tempest/services/compute/json/limits_client.py
+++ b/tempest/services/compute/json/limits_client.py
@@ -21,7 +21,7 @@
 
 class LimitsClientJSON(service_client.ServiceClient):
 
-    def get_absolute_limits(self):
+    def show_limits(self):
         resp, body = self.get("limits")
         body = json.loads(body)
         self.validate_response(schema.get_limit, resp, body)