change ss_voice_files's id: Integer to BSON::ObjectId.
* rename `async` to 'job' and several classes renames.
add some functionarites to job queue.

* can specify num fork
* can specify size limit pool by pool
* can specify dequeue pool
modify html scraper.

* better scraping.
rename 'Worker.rb' to 'worker.rb'
support multiple domains in one site.
modify audio controller position.
support ruby generate different hash for each process.
support multiple domains for each site.
fix lock issue