.travis.yml in roo_on_rails-1.8.0 vs .travis.yml in roo_on_rails-1.8.1

@@ -1,28 +1,34 @@
-sudo: false
+sudo: required
 language: ruby
 rvm:
-  - 2.2.6
+  - 2.2.7
   - 2.3.3
-  - 2.4.0
+  - 2.4.1
   - ruby-head
 gemfile:
   - gemfiles/rails_3.gemfile
   - gemfiles/rails_4.gemfile
   - gemfiles/rails_5.gemfile
   - gemfiles/rails_5_1.gemfile
 install:
   - bundle install --jobs=3 --retry=3 --path=vendor/bundle
 cache:
-  bundler: false
+  bundler: true
   directories:
     - vendor/bundle
+    - vendor/bundle-scaffold
 before_script:
   - unset RACK_ENV
   - unset RAILS_ENV
+  - mkdir -p $PWD/tmp && sudo mount -t tmpfs -o size=1024m tmpfs $PWD/tmp
+  - gem install bundler
 matrix:
   allow_failures:
     - rvm: ruby-head
-    - rvm: 2.4.0
+  exclude:
+    - rvm: 2.4.1
+      gemfile: gemfiles/rails_3.gemfile
+    - rvm: ruby-head
       gemfile: gemfiles/rails_3.gemfile
 services:
   - redis-server