Use new image for kitchen tests

Change-Id: I5c7b8cbb4e8c7d53e397823919f91c3ee05e8c30
diff --git a/.travis.yml b/.travis.yml
index f42fc6d..6d1abb3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,14 +17,12 @@
   - bundle install
 
 env:
-    - PLATFORM=trevorj/salty-whales:trusty-2017.7 SUITE=cluster
-    - PLATFORM=trevorj/salty-whales:xenial-2017.7 SUITE=cluster
-    - PLATFORM=trevorj/salty-whales:trusty-2017.7 SUITE=single
-    - PLATFORM=trevorj/salty-whales:xenial-2017.7 SUITE=single
-    - PLATFORM=trevorj/salty-whales:trusty SUITE=cluster
-    - PLATFORM=trevorj/salty-whales:xenial SUITE=cluster
-    - PLATFORM=trevorj/salty-whales:trusty SUITE=single
-    - PLATFORM=trevorj/salty-whales:xenial SUITE=single
+    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 SUITE=cluster
+    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 SUITE=single
+    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 SUITE=cluster
+    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 SUITE=single
+#    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-bionic-salt-2017.7 SUITE=cluster
+#    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-bionic-salt-2017.7 SUITE=single
 
 before_script:
   - set -o pipefail