Using of deprecated method removed

After installing this gem i have this note:

```
NOTE: Gem.searcher is deprecated, use Specification. It will be removed on or after 2011-11-01.
Gem.searcher called from /home/vagrant/.rvm/gems/ruby-1.9.3-p374/bundler/gems/GreenMidget-52ebfdc6aa83/lib/green_midget.rb:23.
NOTE: Gem::GemPathSearcher#initialize is deprecated with no replacement. It will be removed on or after 2011-10-01.
Gem::GemPathSearcher#initialize called from /home/vagrant/.rvm/rubies/ruby-1.9.3-p374/lib/ruby/1.9.1/rubygems.rb:974.
NOTE: Gem::GemPathSearcher#find is deprecated with no replacement. It will be removed on or after 2011-10-01.
Gem::GemPathSearcher#find called from /home/vagrant/.rvm/gems/ruby-1.9.3-p374/bundler/gems/GreenMidget-52ebfdc6aa83/lib/green_midget.rb:23.
```

I've fix this bug