Update gem requirements for travis

.travis.yml

@@ -4,18 +4,29 @@ sudo: false
 fast_finish: true
 script: rake $RUN
 
+before_install:
+  # thanks to https://mediocre.com/forum/topics/phantomjs-2-and-travis-ci-we-beat-our-heads-against-a-wall-so-you-dont-have-to
+  - wget https://s3.amazonaws.com/travis-phantomjs/phantomjs-2.0.0-ubuntu-12.04.tar.bz2
+  - tar -xjf phantomjs-2.0.0-ubuntu-12.04.tar.bz2
+  # Keep track of which version of phantomjs we're running the specs against
+  - phantomjs -v
+
 matrix:
   include:
-    - rvm: 2.2
-    - rvm: 2.1
-    - rvm: 1.9.3
-    - rvm: 2.0
+    - rvm: 2.3.1
+      env: PATH=".:$PATH"
+    - rvm: 2.2.4
+      env: PATH=".:$PATH"
+    - rvm: 2.1.10
+      env: PATH=".:$PATH" RACK_VERSION='< 2.0'
+    - rvm: 2.0.0
+      env: PATH=".:$PATH" RACK_VERSION='< 2.0'
 
-    # We use 2.1.4 to differentiate the rvm version
+    # We use 2.1.9 to differentiate the rvm version
     # as travis doesn't allow failures by env.
-    - rvm: 2.1.4
-      env: RUN=zepto
+    - rvm: 2.1.9
+      env: RUN=zepto PATH=".:$PATH" RACK_VERSION='< 2.0'
 
   allow_failures:
-    - rvm: 2.1.4
+    - rvm: 2.1.9
 

Gemfile

@@ -1,4 +1,6 @@
 source 'https://rubygems.org'
 gemspec
+
 gem 'opal', ENV['OPAL_VERSION'] || '~> 0.10.0'
 gem 'opal-rspec', github: 'opal/opal-rspec', submodules: true
+gem 'rack', ENV['RACK_VERSION'] || '> 0'