[AETHER-444] Improves tost CI/CD jobs

- the jobs are now private (new templates are added)
- docker login is done conditionally if username and password are defined
- docker credentials are added to the private-make-test template
- omecproject credentials are added to the private-make-test template
- withDockerRegistry and withCredentials are added to the build steps

Change-Id: I5233d12138d486075895e5e50baafd06a68ea04c
diff --git a/jjb/repos/tost-onos.yaml b/jjb/repos/tost-onos.yaml
index 2097a9c..453d1ee 100644
--- a/jjb/repos/tost-onos.yaml
+++ b/jjb/repos/tost-onos.yaml
@@ -19,7 +19,7 @@
       - 'verify-licensed'
       - 'tag-check':
           dependency-jobs: 'license-check_tost-onos'
-      - 'make-test':
+      - 'private-make-test':
           make-test-vars: |
             ONOS_BRANCH=onos-2.2
           make-test-targets: 'docker-build'
@@ -29,7 +29,7 @@
 - job-group:
     name: 'publish-tost-onos-jobs'
     jobs:
-      - 'docker-publish':
+      - 'private-docker-publish':
           docker-repo: 'onosproject'
           maintainers: 'charles@opennetworking.org, pier@opennetworking.org'
           build-timeout: 30