Disable and remove OracleLinux CI jobs

We have agreed to remove support for Oracle Linux, starting by disabling
the CI jobs.

http://lists.openstack.org/pipermail/openstack-discuss/2019-June/006896.html

Change-Id: Ic7e7bedf36f98e3f7a0e2a22ec76136f4414c765

.zuul.d/oraclelinux.yaml

@@ -1,58 +0,0 @@
----
-- project:
-    check:
-      jobs:
-        - kolla-build-oraclelinux-binary
-        - kolla-build-oraclelinux-source
-        - kolla-ansible-oraclelinux-source
-        - kolla-ansible-oraclelinux-binary
-        - kolla-ansible-oraclelinux-source-ceph:
-            files: ^docker\/(ceph|cinder)\/.*
-    gate:
-      jobs:
-        - kolla-build-oraclelinux-source
-    periodic:
-      jobs:
-        - kolla-publish-oraclelinux-source
-        - kolla-publish-oraclelinux-binary
-    release:
-      jobs:
-        - kolla-publish-oraclelinux-source
-        - kolla-publish-oraclelinux-binary
-
-- job:
-    name: kolla-build-oraclelinux-binary
-    parent: kolla-base
-    nodeset: kolla-centos
-    voting: false
-    vars:
-      action: build
-      base_distro: oraclelinux
-      install_type: binary
-
-- job:
-    name: kolla-publish-oraclelinux-binary
-    parent: kolla-build-oraclelinux-binary
-    post-run: tests/playbooks/publish.yml
-    vars:
-      publisher: true
-    secrets:
-      - kolla_dockerhub_creds
-
-- job:
-    name: kolla-build-oraclelinux-source
-    parent: kolla-base
-    nodeset: kolla-centos
-    vars:
-      action: build
-      base_distro: oraclelinux
-      install_type: source
-
-- job:
-    name: kolla-publish-oraclelinux-source
-    parent: kolla-build-oraclelinux-source
-    post-run: tests/playbooks/publish.yml
-    vars:
-      publisher: true
-    secrets:
-      - kolla_dockerhub_creds