Log Message:
Update ruby-parallel to 1.12.0.

1.10.0						2016/11/24

* add Readme docs for .worker_number
* Do not call kill method if thread is nil
* Adds comment to readme for trappig TERM
* make undumpable exceptions traceable

1.11.0						2017/03/11

* make version not be required twice when using via git source
* Simplify Array initialization with slight performance improvement
* Added failing tests for handling Parallel::Break in work_direct
* Handle kill and break exceptions in work_direct (closes #128 and #130)
* Replace "rescue StandardError" with "rescue ... $!"
* Added any? and all?

1.11.1						2017/03/12

* Fix typo (bracktrace => backtrace), and use attr_reader
* Added failing test to simulate stack trace added by better_errors gem
* Remove bindings stack that is added by the better_errors gem

1.11.2						2017/05/07

* syncronize worker replacement to avoid #196

1.12.0						2017/07/25

* Update to rails 4.2.8 or higher for ruby 2.4 support
* Run bundle update to fix some errors and warnings.
* Reference the Tempfile so it's not GC'd/removed too early
* use Tempfile.open for automatic cleanup
* fix #149