Merge pull request #483 from donv/patch-1

Update JRuby version to 9.2.8.0 + remove EOL Ruby 2.2

.travis.yml

 sudo: false
 language: ruby
-before_install: gem update --system
+before_install:
+  - gem query -I -n "^bundler$" -v ">=2" || gem uninstall -x bundler -v ">=2" || rvm @global do gem uninstall -x bundler -v ">=2"
+  - gem query -i -n "^bundler$" -v "<2" || gem install bundler -v "<2"
 cache: bundler
 rvm:
-  - 2.2
   - 2.3.8
   - 2.4.5
   - 2.5.3
   - 2.6.3
-  - jruby-9.1.6.0
+  - jruby-9.2.8.0
 
 env:
   matrix:
@@ -21,18 +22,16 @@ env:
 matrix:
   allow_failures:
     - env: RAILS='~> 4.2.0' SQLITE_VERSION='~> 1.3.6'
-      rvm: jruby-9.1.6.0
+      rvm: jruby-9.2.8.0
     - env: RAILS='~> 5.0.0' SQLITE_VERSION='~> 1.3.6'
-      rvm: jruby-9.1.6.0
+      rvm: jruby-9.2.8.0
     - env: RAILS='~> 5.1.0'
-      rvm: jruby-9.1.6.0
+      rvm: jruby-9.2.8.0
     - env: RAILS='~> 5.2.0'
-      rvm: jruby-9.1.6.0
+      rvm: jruby-9.2.8.0
     - env: RAILS='master'
-      rvm: jruby-9.1.6.0
+      rvm: jruby-9.2.8.0
   exclude:
-    - rvm: 2.2
-      env: RAILS='master'
     - rvm: 2.3.8
       env: RAILS='master'
     - rvm: 2.4.5