.travis.yml in rbnacl-5.0.0 vs .travis.yml in rbnacl-6.0.0

@@ -1,25 +1,25 @@
 language: ruby
-sudo: false
 cache: bundler
-script: bundle exec rake ci
-bundler_args: --without development
 
-branches:
-  only:
-    - master
+before_install:
+  - sudo add-apt-repository -y ppa:chris-lea/libsodium
+  - sudo apt-get update -q
+  - sudo apt-get install libsodium-dev
+  - gem update --system
+  - gem --version
+  - gem install bundler -v 1.17.1
+  - bundle --version
 
 rvm:
-  - jruby-9.1.6.0
-  - 2.2.6
-  - 2.3.3
-  - 2.4.0
+  - jruby-9.1.15.0
+  - 2.2
+  - 2.3
+  - 2.4
+  - 2.5
 
-env:
-  - LIBSODIUM_VERSION=1.0.0  # Minimum supported
-  - LIBSODIUM_VERSION=1.0.11 # Latest released
-
 matrix:
   fast_finish: true
 
-notifications:
-  irc: "irc.freenode.org#cryptosphere"
+branches:
+  only:
+    - master