Make it possible to run zuul layout test locally

Add a tox environment to run the zuul layout tests locally.

Modify run-layout.sh to ignore a missing mirror selection script
and assume that it is running with a valid mirror configuration.
This allows the script to be run locally without breaking a
dev environment.

Change-Id: I5b0c94ae51e7f41b8b26b3ef4f78b830031d263e

tools/run-layout.sh

@@ -25,7 +25,13 @@ then
   echo "PROJECT: The project name (eg 'nova')"
   exit 1
 else
-  /usr/local/jenkins/slave_scripts/select-mirror.sh $org $project
+  if [ -f /usr/local/jenkins/slave_scripts/select-mirror.sh ]
+  then
+      /usr/local/jenkins/slave_scripts/select-mirror.sh $org $project
+  else
+      echo "No mirror script /usr/local/jenkins/slave_scripts/select-mirror.sh,"
+      echo "assuming local environment is configured properly."
+  fi
 fi
 
 mkdir -p .test

tox.ini

@@ -39,3 +39,11 @@ commands =
   rm -rf {envdir}/tmp
   mkdir -p {envdir}/tmp
   jenkins-jobs -l debug test -o {envdir}/tmp modules/openstack_project/files/jenkins_job_builder/config
+
+[testenv:zuul]
+basepython = python2.7
+deps =
+commands =
+  {toxinidir}/tools/check_projects_yaml_alphabetized.sh
+  {toxinidir}/tools/run-layout.sh openstack-infra config
+