CYB-74, CYB-86.  Adding background worker process and first worker

* Uses the sidekiq background processing framework, and sidetiq for period job execution
* Adds a thor task to kick the job off manually
* Requires Redis
* Updates README.md file with latest instructions
Merge pull request #31 from coyote/background_services

CYB-74, CYB-86.  Adding background worker process and first worker