Merge branch 'zj-rename-ci-vars' into 'master'

.gitlab-ci.yml

config/initializers/rspec_profiling.rb

doc/ci/docker/using_docker_build.md

doc/ci/environments.md

doc/ci/review_apps/index.md

doc/ci/variables/README.md

doc/ci/yaml/README.md

doc/user/project/new_ci_build_permissions_model.md

lib/tasks/gitlab/dev.rake

spec/lib/expand_variables_spec.rb

spec/lib/gitlab/ci/config/entry/environment_spec.rb

spec/models/environment_spec.rb

spec/requests/api/runner_spec.rb

spec/requests/ci/api/builds_spec.rb

spec/services/ci/create_pipeline_service_spec.rb

spec/services/create_deployment_service_spec.rb

spec/simplecov_env.rb