attempt to improve travis perf

.travis.yml

@@ -1,25 +1,27 @@
 language: ruby
+sudo: false
 cache: bundler
-bundler_args: --without development
-before_install: git submodule update --init --recursive
+before_script:
+  - bundle update
 rvm:
   - ruby-head
   - jruby-19mode
+  - rbx-2
   - 2.2
-  - 2.1.5
-  - 2.1.4
-  - 2.1.3
-  - 2.1.2
-  - 2.1.1
-  - 2.1.0
-  - 2.0.0
+  - 2.1
+  - 2.0
   - 1.9.3
 matrix:
   fast_finish: true
   allow_failures:
     - rvm: ruby-head
     - rvm: jruby-19mode
-env: TEST=true CODECLIMATE_REPO_TOKEN=81787f7b1c3bfa937edadcafbc94f807bf5af5c1142c7b793f2d9969a271de1f 
+    - rvm: rbx-2
+env:
+  global:
+    - JRUBY_OPTS='-J-Xmx1024M'
+    - TEST=true
+    - CODECLIMATE_REPO_TOKEN=81787f7b1c3bfa937edadcafbc94f807bf5af5c1142c7b793f2d9969a271de1f 
 script: bundle exec rake test
 notifications:
   slack: middleman:JW9OvXmn1m3XrSERe8866nBR