Add newly added cached apt repositories.
Add blog post on hip hop.
Merge pull request #429 from travis-ci/mm-hip-hop

Add blog post on hip hop.
Minor fixes for HHVM blog post
Add a thank you to Loic.
Thanks all you awesome services blog post!
Update CloudAMQP link
Indenting the code example for s3 multiple-bucket deployment

so that it is syntax highlighted and monospace rather than flowing from
the preceding sentence.
docs(deploy-s3): fix indentation for code samples
Fix spelling mistake

runnig -> running
Merge pull request #433 from daxtens/patch-1

Fix spelling mistake
Updating the docs in order to clarify that Gradle was upgraded to 1.8.
Merge pull request #434 from thedrow/patch-2

Updating the docs in order to clarify that Gradle was upgraded to 1.8
Gradle version is 1.9
Add detail on specifying multiple GHC versions.
Fix link to klein project.
Rewrite chunks of the Ruby documentation.

Keeps it more up-to-date with information relevant to most users
of Travis CI, incl. Ruby versions, some Bundler hacks and other goodies.

Removes a few things that were historically included and updated them
with writing that makes more sense with our current setup.
Add section on Bundler caching.
Add explanation how the caching works.
Slightly more detail on Rubinius.