Use new image for kitchen tests

Change-Id: I7ad7ea5e4650ed046f29812de04d215146a755b4
diff --git a/.travis.yml b/.travis.yml
index 9905c44..ebd5938 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -17,10 +17,12 @@
   - bundle install
 
 env:
-  - PLATFORM=trevorj/salty-whales:trusty SUITE=openssh-client
-  - PLATFORM=trevorj/salty-whales:xenial SUITE=openssh-client
-  - PLATFORM=trevorj/salty-whales:trusty SUITE=openssh-server
-  - PLATFORM=trevorj/salty-whales:xenial SUITE=openssh-server
+  - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 SUITE=openssh-client
+  - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2016.3 SUITE=openssh-server
+  - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 SUITE=openssh-client
+  - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-xenial-salt-2017.7 SUITE=openssh-server
+  # - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-bionic-salt-2017.7 SUITE=openssh-client
+  # - PLATFORM=epcim/salt-formulas:saltstack-ubuntu-bionic-salt-2017.7 SUITE=openssh-server
 
 before_script:
   - set -o pipefail