Added tempest subcommand for subunit_describe_calls

We are adding a subcommand to tempest that is a parser for subunit
streams to determine what REST API calls are made inside of a test
and in what order they are called. Right now the implementation of
utility is as a console script and which is in argparse.

We are porting it to cliff to give a similar experience across
the codebase.

Change-Id: If95042898d8b2a148246c991d73d1a577fbcf7a0
Signed-off-by: Soniya Vyas <svyas@redhat.com>
diff --git a/setup.cfg b/setup.cfg
index 5c1d24c..1e9b8e9 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -36,6 +36,7 @@
     subunit-describe-calls = tempest.cmd.subunit_describe_calls:entry_point
 tempest.cm =
     account-generator = tempest.cmd.account_generator:TempestAccountGenerator
+    subunit-describe-calls = tempest.cmd.subunit_describe_calls:TempestSubunitDescribeCalls
     init = tempest.cmd.init:TempestInit
     cleanup = tempest.cmd.cleanup:TempestCleanup
     list-plugins = tempest.cmd.list_plugins:TempestListPlugins