Adding some documentation about using the artifacts addon
Add commentary on group membership

Basically a do-over of https://github.com/travis-ci/travis-ci.github.com/pull/441
Remove mention of after_install.
deployment/s3: Correct typo
Document `deploy.on` as common option for all deployments
Merge pull request #79 from duggiefresh/gh-pages

deployment/s3: Correct typo
add another codeclimate example
Explain use of .ruby-version
Synchronize env vars for Linux and OS X workers

While `$TRAVIS_OS_NAME` should be set for non-multi-os builds
(https://github.com/travis-ci/travis-ci/issues/2384), for now,
do not guarantee that it is set for them.

Also addresses the lack of documentation that led to
https://github.com/travis-ci/travis-ci/issues/2411.
Add TravisWall dashboard for public/private repos
Merge pull request #81 from egeloen/travis-wall

Add TravisWall dashboard for public/private repos
Document Content-Encoding feature for S3
Fix typo in S3 doc
Merge branch 'gh-pages' of github.com:travis-ci/docs-travis-ci-com into gh-pages
Fix $TRAVIS_TEST_RESULT
Update OTP releases available
Update jquery_ui.js
Update jquery.tocify.js
Update en.html
Update Code Climate documenation

Code Climate code coverage feature is now available for free
accounts (https://codeclimate.com/changelog/5343fd41e30ba0098100d1eb)

Reported by Graham Wagener