requests can be "lost" because [].shift is nil
this means that when all workers are busy they can lose
a request that comes in when it tries to shift off a worker

this PR adds a local queue that will queue that request until
a worker is available to work that queue
move process local before poll call
Merge pull request #189 from localshred/bdewitt/queued_requests

requests can be "lost" because [].shift is nil
Bump version 3.0.2