first pass of parallelization

[jtushman]

[Do not merge]

first pass of adding parallelization

• adding hooks for before.batch and after.batch (think I should rename to before.fork and after.hook)
• added a new runner -- ParallelRunner, which loops over all of the scenarios (not the features) batches them up for n workers to have at them, then joins the threads and regroups the scenarios into featureResults
• adds option --parallel / -p which you can pass -n- for the number of processes you want to have processing your tests

but with these hooks the implementer can set up there forked process. I also set a world.port_number for the implementer to use that to setup webservers and other resources specifically to each fork.

Still very much in beta -- and I have some ideas to make it faster -- but seems promising

Known issues:

• need docs
• need tests

Love Feedback -- is this something that you would consider pulling in. If so I can work on the known issues, and other feedback that you might have.

Happy Holidays!

[ashrafuzzaman]

Guys what is the update on this issue. It would be great to run tests in parallel.