add detection of ActiveRecord connection and use it
add WIP test for ActiveRecord connection detection
add spec for ActiveRecord connection detection
make ActiveRecord detection work on Ruby 2.0.x
update README with Rails DB connection detection
remove useless ensure
add QC_RAILS_DATABASE to disable conn detection
add note in README regarding Active Job
Merge branch 'master' into detect-rails-db-connection
Merge pull request #232 from jipiboily/detect-rails-db-connection

detect Rails DB connection and use it