.travis.yml in omniauth-1.7.1 vs .travis.yml in omniauth-1.8.0

@@ -1,7 +1,9 @@
 bundler_args: --without development
-before_install: gem update bundler
+before_install:
+  - gem update --system
+  - gem update bundler
 cache: bundler
 env:
   global:
     - JRUBY_OPTS="$JRUBY_OPTS --debug"
 language: ruby
@@ -9,9 +11,10 @@
   - jruby-9000
   - 2.1.10 # EOL Soon
   - 2.2.6
   - 2.3.3
   - 2.4.0
+  - 2.5.0
   - jruby-head
   - ruby-head
 matrix:
   allow_failures:
     - rvm: jruby-head