Bump rails-observers required version
Adding `lib/activeresource.rb` to the project.

This allows to remove the `require: active_resource` from the Gemfile
and just use `gem 'activeresource'`.
Updating changelog.
Merge pull request #95 from lunks/add-activeresource-file

Adding `lib/activeresource.rb` to the project.
Update API doc url. Fix #110.
Merge pull request #112 from ericlathrop/update-api-doc-url

Update API doc url. Fix #110.
Change Gemfile to point Rails 4-0-stable branch.
Test against released gem.
Revert "Test against released gem."

This reverts commit 8bcc99e351287bfc0032da087396b58717f0ae78.

This change should be done in the 4-0-stable branch.
Test against Rails master.
Ignore *.lock files.
Update Rubinius Modes
travis-ci/travis-ci#1641
Merge pull request #113 from robertomiranda/update-rubinius-mode

Update Rubinius Modes