Add CHANGELOG.
Adds installation of Riak 2.x repositories and bumps the playbook
version to 2.0.0
Fixes a race condition between the repo updates triggered for the 1.x and 2.x
repos which caused the 1.x versions to be unavailable
Adds version selection guidance to the README
Merge branch 'riak-2.0-repos' into develop
Merge branch 'develop'