Update travis config with travis command line client & add slack integration

.travis.yml

@@ -1,20 +1,23 @@
 language: ruby
 addons:
-  postgresql: "9.4"
+  postgresql: '9.4'
 rvm:
- - "2.3.2"
+- 2.3.2
 cache: bundler
 bundler_args: --without development
 before_script:
-  - "for i in config/*.example; do cp \"$i\" \"${i/.example}\"; done"
-  - bundle exec rake db:setup
+- for i in config/*.example; do cp "$i" "${i/.example}"; done
+- bundle exec rake db:setup
 script:
-  - "bundle exec rake assets:precompile RAILS_ENV=test"
-  - "bin/knapsack_pro_rspec"
+- bundle exec rake assets:precompile RAILS_ENV=test
+- bin/knapsack_pro_rspec
 env:
   global:
-    - KNAPSACK_PRO_FIXED_QUEUE_SPLIT=true
-    - KNAPSACK_PRO_CI_NODE_TOTAL=2
+  - KNAPSACK_PRO_FIXED_QUEUE_SPLIT=true
+  - KNAPSACK_PRO_CI_NODE_TOTAL=2
   matrix:
-    - KNAPSACK_PRO_CI_NODE_INDEX=0
-    - KNAPSACK_PRO_CI_NODE_INDEX=1
+  - KNAPSACK_PRO_CI_NODE_INDEX=0
+  - KNAPSACK_PRO_CI_NODE_INDEX=1
+notifications:
+  slack:
+    secure: 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