Rake tasks refactored [passes]

== Changed

* rails_best_practice metric added to the `rake full` task;
* uuids_tasks.rake file refactored to simplify methods.
Allowed Uuid#value setting before object creation [passes]

== Changes

* Uuid#value= method becomes public;
* Uuid#value attribute becomes readonly;
* README.rdoc updated;
* Version changed to 0.1.0 to reflect the new feature.