Add CI test layouts

* Drop Trusty from test matrix
* Add extra cases to test separate roles deployment

Signed-off-by: Bogdan Dobrelya <bdobrelia@mirantis.com>

.travis.yml

@@ -72,19 +72,22 @@ env:
       CLOUD_IMAGE=ubuntu-1604-xenial
       CLOUD_REGION=asia-east1-c
 
-    # Ubuntu 15.10
+    # Extra cases for separated roles
     - >-
       KUBE_NETWORK_PLUGIN=flannel
-      CLOUD_IMAGE=ubuntu-1510-wily
+      CLOUD_IMAGE=rhel-7-sudo
       CLOUD_REGION=europe-west1-b
+      MODE="separate"
     - >-
       KUBE_NETWORK_PLUGIN=calico
-      CLOUD_IMAGE=ubuntu-1510-wily
+      CLOUD_IMAGE=ubuntu-1604-xenial
       CLOUD_REGION=us-central1-a
+      MODE="separate"
     - >-
       KUBE_NETWORK_PLUGIN=weave
-      CLOUD_IMAGE=ubuntu-1510-wily
+      CLOUD_IMAGE=debian-8-kubespray
       CLOUD_REGION=us-east1-d
+      MODE="separate"
 
 
 before_install:
@@ -113,6 +116,7 @@ before_script:
 script:
   - >
     $HOME/.local/bin/ansible-playbook tests/cloud_playbooks/create-gce.yml -i tests/local_inventory/hosts -c local $LOG_LEVEL
+    -e mode=${MODE}
     -e test_id=${TEST_ID}
     -e kube_network_plugin=${KUBE_NETWORK_PLUGIN}
     -e gce_project_id=${GCE_PROJECT_ID}