Revert "Test travis config"

This reverts commit 5ad4f9d.

I definitely did not mean to make this change on master! EEP!

.travis.yml

@@ -3,26 +3,25 @@ env:
   - ARUBA_TIMEOUT=240
 before_install:
   - gem update --system
-  - gem update bundler
-  - gem cleanup bundler
+  - rvm @default,@global do gem uninstall bundler -v 2.0.2 -x
 cache: bundler
 rvm:
   - 2.3
-  # - 2.4
-  # - 2.5
-  # - 2.6
-  # - ruby-head
+  - 2.4
+  - 2.5
+  - 2.6
+  - ruby-head
 branches:
   only:
     - master
 install:
   - "bundle install --retry 3 --jobs 8"
 gemfile:
   - gemfiles/rails4.2.gemfile
-  # - gemfiles/rails5.0.gemfile
-  # - gemfiles/rails5.1.gemfile
-  # - gemfiles/rails5.2.gemfile
-  # - gemfiles/rails6.0.gemfile
+  - gemfiles/rails5.0.gemfile
+  - gemfiles/rails5.1.gemfile
+  - gemfiles/rails5.2.gemfile
+  - gemfiles/rails6.0.gemfile
 matrix:
   fast_finish: true
   allow_failures: