Log Message:
Update ruby-rspec-core to 3.6.0.

### 3.6.0 / 2017-05-04
[Full Changelog](http://github.com/rspec/rspec-core/compare/v3.6.0.beta2...v3.6.0)

Enhancements:

* Add seed information to JSON formatter output. (#2388, Mitsutaka Mimura)
* Include example id in the JSON formatter output. (#2369, Xavier Shay)
* Respect changes to `config.output_stream` after formatters have been
  setup. (#2401, #2419, Ilya Lavrov)

Bug Fixes:

* Delay formatter loading until the last minute to allow accessing the reporter
  without triggering formatter setup. (Jon Rowe, #2243)
* Ensure context hook failures running before an example can access the
  reporter. (Jon Jensen, #2387)
* Multiple fixes to allow using the runner multiple times within the same
  process: `RSpec.clear_examples` resets the formatter and no longer clears
  shared examples, and streams can be used across multiple runs rather than
  being closed after the first. (#2368, Xavier Shay)
* Prevent unexpected `example_group_finished` notifications causing an error.
  (#2396, VTJamie)
* Fix bugs where `config.when_first_matching_example_defined` hooks would fire
  multiple times in some cases. (Yuji Nakayama, #2400)
* Default `last_run_status` to "unknown" when the `status` field in the
  persistence file contains an unrecognized value. (#2360, matrinox)
* Prevent `let` from defining an `initialize` method. (#2414, Jon Rowe)

### 3.6.0.beta2 / 2016-12-12
[Full \ 
Changelog](http://github.com/rspec/rspec-core/compare/v3.6.0.beta1...v3.6.0.beta2)

Enhancements:

* Include count of errors occurring outside examples in default summaries.
  (#2351, Jon Rowe)
* Warn when including shared example groups recursively. (#2356, Jon Rowe)
* Improve failure snippet syntax highlighting with CodeRay to highlight
  RSpec "keywords" like `expect`. (#2358, Myron Marston)

### 3.6.0.beta1 / 2016-10-09
[Full Changelog](http://github.com/rspec/rspec-core/compare/v3.5.4...v3.6.0.beta1)

Enhancements:

* Warn when duplicate shared examples definitions are loaded due to being
  defined in files matching the spec pattern (e.g. `_spec.rb`) (#2278, Devon Estes)
* Improve metadata filtering so that it can match against any object
  that implements `===` instead of treating regular expressions as
  special. (Myron Marston, #2294)
* Improve `rspec -v` so that it prints out the versions of each part of
  RSpec to prevent confusion. (Myron Marston, #2304)
* Add `config.fail_if_no_examples` option which causes RSpec to fail if
  no examples are found. (Ewa Czechowska, #2302)
* Nicely format errors encountered while loading spec files.
  (Myron Marston, #2323)
* Improve the API for enabling and disabling color output (Josh
  Justice, #2321):
  * Automatically enable color if the output is a TTY, since color is
    nearly always desirable if the output can handle it.
  * Introduce new CLI flag to force color on (`--force-color`), even
    if the output is not a TTY. `--no-color` continues to work as well.
  * Introduce `config.color_mode` for configuring the color from Ruby.
    `:automatic` is the default and will produce color if the output is
    a TTY. `:on` forces it on and `:off` forces it off.