Log Message:
Update ruby-rspec-rails to 3.4.0.

### 3.4.0 / 2015-11-11
[Full Changelog](http://github.com/rspec/rspec-rails/compare/v3.3.3...v3.4.0)

Enhancements:

* Improved the failure message for `have_rendered` matcher on a redirect
  response. (Alex Egan, #1440)
* Add configuration option to filter out Rails gems from backtraces.
  (Bradley Schaefer, #1458)
* Enable resolver cache for view specs for a large speed improvement
  (Chris Zetter, #1452)
* Add `have_enqueued_job` matcher for checking if a block has queued jobs.
  (Wojciech Wnętrzak, #1464)

Bug Fixes:

* Fix another load order issued which causes an undefined method `fixture_path` error
  when loading rspec-rails after a spec has been created. (Nikki Murray, #1430)
* Removed incorrect surrounding whitespace in the rspec-rails backtrace
  exclusion pattern for its own `lib` code. (Jam Black, #1439)