denormalize_to: inverse_of used instead of class name for prefixing fields to update
Gemfile and Guardfile added.
#denormalize_to performances increased.
Performance measure tool added.
Merge branch 'master' of git://github.com/suruja/mongoid_denormalize into feature/obey_inverse_of

Conflicts:
	lib/mongoid_denormalize.rb
	spec/app/models/user.rb
	spec/mongoid_denormalize_spec.rb