.travis.yml in jekyll-gzip-2.0.0 vs .travis.yml in jekyll-gzip-2.1.0

@@ -1,9 +1,14 @@
 sudo: false
 language: ruby
 rvm:
+  - 2.6
   - 2.5
   - 2.4
   - 2.3
-  - 2.2
-before_install: gem install bundler -v 1.16.1
+  - ruby-head
+matrix:
+  allow_failures:
+    - rvm: ruby-head
+
+before_install: gem install bundler
 script: bundle exec rspec
\ No newline at end of file