[FEATURE] Uuids::Base.has_uuids defines the #uuids= method [passes]

Now it's possible to assign a list of uuids values at once.

== Changes

* Uuids::Base class refactored. All methods and callbacks added by
  Uuids::Base.has_uuids are extracted to Uuids::Base::HasUuids module.

== Addons

* Uuids::Base::HasUuids#uuids=(*values).

== Version

New release 1.3.0