Create tox-pep8 jobs

Because we want to use tox role variables (tox_envlist) across
multiple plays. We need to setup the variable in zuul.yaml.  However,
this now means we need to create tox-pep8 job now since we are using
the tox/run playbook.

Change-Id: I6c15c076a510375dfacc66a0e07bc3f1228adf06
Signed-off-by: Paul Belanger <pabelanger@redhat.com>

playbooks/tox/linters.yaml

@@ -1,20 +0,0 @@
-- hosts: all
-  pre_tasks:
-    - name: Register tox environment list
-      command: tox -l
-      args:
-        chdir: "src/{{ zuul.project.canonical_name }}"
-      register: envlist
-
-    - name: Define tox_envlist fact for pep8
-      set_fact:
-        tox_envlist: 'pep8'
-      when: envlist.stdout.find('pep8') != -1
-
-    - name: Define tox_envlist fact for linters
-      set_fact:
-        tox_envlist: 'linters'
-      when: envlist.stdout.find('linters') != -1
-
-  roles:
-    - tox

zuul.yaml

@@ -85,7 +85,18 @@
       Runs code linting tests.
 
       Uses tox with the "linters" environment.
-    run: playbooks/tox/linters
+    vars:
+      tox_envlist: linters
+
+- job:
+    name: tox-pep8
+    parent: tox
+    description: |
+      Runs code pep8 tests.
+
+      Uses tox with the "pep8" environment.
+    vars:
+      tox_envlist: pep8
 
 - job:
     name: tox-cover