Use new image for kitchen tests

Change-Id: I130fba8eb49f6ed5ccff7834189c462cd7a23dfb
diff --git a/.travis.yml b/.travis.yml
index 653f024..5119179 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,10 +17,12 @@
   - bundle install
 
 env:
-  - 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