= wested/acts_as_versioned
This library expands acts_as_versioned to always track the datetime the
version was created (versioned_at) and the datetime that that version was no
longer current (version_expired_at).
An `existing_at(datetime)` named scope is added to the version models, making
it possible to do fancy things like scope, or apply to associations:
pages = author.page_versions.existing_at(datetime)
Additionally, a simple accessor is created in the versioned model:
page.version_at(datetime)
See the TODO file for the immediate next steps, as well as a thought about
a potentially nice approach for doing things like
@author.version_at(datetime).pages
and having the pages that are returned be the page versions that existed at
datetime.