2.14.0 DeprecationFormatter errors when using ruby-debug

It looks like new DeprecationFormatter doesn't implement start method, so the call is routed to the Kernel method, that is injected by ruby-debug and has a different signature.

```Ruby
module Kernel
  def start(options={}, &block)
  ......
  end
end


class BaseFormatter
   def start(example_count)
   ....
   end
end
```

Error Message:

```
TypeError: can't convert Fixnum into Hash
     merge at org/jruby/RubyHash.java:1756
     start at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/ruby-debug-base-0.10.4-java/lib/ruby-debug-base.rb:205
  __send__ at org/jruby/RubyBasicObject.java:1709
      send at org/jruby/RubyKernel.java:2213
    notify at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/reporter.rb:127
      each at org/jruby/RubyArray.java:1617
    notify at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/reporter.rb:126
     start at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/reporter.rb:66
    report at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/reporter.rb:56
       run at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/command_line.rb:25
       run at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/runner.rb:80
   autorun at /Users/aportnov/.rvm/gems/jruby-1.7.4@hockey-core/gems/rspec-core-2.14.0/lib/rspec/core/runner.rb:17
```