some possible improvements to build times

- use our new infrastructure based on LXC and EC2
- enable caching for bundler
- use schema:load (best practice)
- use --deployment (best practice when a Gemfile.lock is around)

.travis.yml

@@ -1,16 +1,28 @@
 language: ruby
+
 rvm:
   - 2.0.0
-  - 2.1.2
+  - 2.1
+
+services:
+  - redis-server
+
+sudo: false
+
+cache: bundler
+
+env:
+  - DISCOURSE_HOSTNAME=www.example.com
+  - RUBY_GC_MALLOC_LIMIT=50000000
+
 before_install:
   - npm i -g jshint
   - jshint .
+
 before_script:
   - psql -c 'create database discourse_test;' -U postgres
-  - export DISCOURSE_HOSTNAME=www.example.com
-  - export RUBY_GC_MALLOC_LIMIT=50000000
-  - bundle exec rake db:migrate
-bundler_args: --without development
+  - bundle exec rake db:schema:load
+
+bundler_args: --without development --deployment
+
 script: 'bundle exec rspec && bundle exec rake plugin:spec && bundle exec rake qunit:test'
-services:
-  - redis-server