NoMethodError (undefined method `collect' for nil:NilClass):

This gem produces a NoMethodError right out of the box:
- set up like in README
- create simple controller and method
- raise Exception, 'bogus' 

Exception: 
```NoMethodError (undefined method `collect' for nil:NilClass):
       whoops_rails_logger (0.1.15) lib/whoops_rails_logger/exception_strategy.rb:46:in `block in add_message_builders`
       whoops_logger (0.1.4) lib/whoops_logger/strategy.rb:32:in `call'```

Solution is attached in code.