Remove Article -> ArticleVersion delegates

[lentschi]

As soon as all callers refer directly to article_version for their fields, remove those delegates:

foodsoft_hackathon/app/models/article.rb

Line 74 in bb044e6

# TODO-article-version: Discuss if these delegates aren't actually a code smell:

For example instead of calling article.name we should be calling article.latest_article_version.name.
Finding all those calls in an untyped language might be quite some effort though.