Add generic base and base-test jobs/playbooks

Start with a stripped-down fork of the base job from project-config,
omitting any OpenStack-specific roles and variables. Also include a
duplicate base-test job intended for testing out potential changes
to the base job.

Change-Id: I575be518c3e549a51c0c94deb295061dcf8be0b5

playbooks/base-test/post-ssh.yaml

@@ -0,0 +1,3 @@
+- hosts: all
+  roles:
+    - remove-build-sshkey

playbooks/base-test/pre.yaml

@@ -0,0 +1,5 @@
+- hosts: all
+  roles:
+    - add-build-sshkey
+    - start-zuul-console
+    - prepare-workspace

playbooks/base/post-ssh.yaml

@@ -0,0 +1,3 @@
+- hosts: all
+  roles:
+    - remove-build-sshkey

playbooks/base/pre.yaml

@@ -0,0 +1,5 @@
+- hosts: all
+  roles:
+    - add-build-sshkey
+    - start-zuul-console
+    - prepare-workspace

zuul.yaml

@@ -0,0 +1,28 @@
+- job:
+    name: base
+    parent: null
+    description: |
+      The recommended base job.
+
+      All jobs ultimately inherit from this.  It runs a pre-playbook
+      which copies all of the job's prepared git repos on to all of
+      the nodes in the nodeset.
+
+      It also sets a default timeout value (which may be overidden).
+    pre-run: playbooks/base/pre.yaml
+    post-run: playbooks/base/post-ssh.yaml
+    roles:
+      - zuul: openstack-infra/zuul-jobs
+    timeout: 1800
+
+- job:
+    name: base-test
+    parent: null
+    description: |
+      A job to test changes to the base job without disturbing the
+      main job in production.  Not for general use.
+    pre-run: playbooks/base-test/pre.yaml
+    post-run: playbooks/base-test/post-ssh.yaml
+    roles:
+      - zuul: openstack-infra/zuul-jobs
+    timeout: 1800