Use new image for kitchen tests

Change-Id: Iaf7ed8fb0d9432e07d1c1766959397978171cd16
diff --git a/.travis.yml b/.travis.yml
index c8e134d..a08c030 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,8 +17,9 @@
   - bundle install
 
 env:
-    - PLATFORM=trevorj/salty-whales:trusty SUITE=server
-    - PLATFORM=trevorj/salty-whales:xenial SUITE=server
+    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 SUITE=server
+    - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 SUITE=server
+    # - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-bionic-salt-2017.7 SUITE=server
 
 before_script:
   - set -o pipefail