Define new content view for 'library'

[lukaszstolarczuk]

Each new repository that would like to have a separate microsite (sub-page) is required to write single.html and lists.html views. We should probably define a new content view "library", re-name/remove existing views, and most likely, unify 'single' view for all our microsites (required for articles/manpages/...).

We have to copy-paste now, quite a lot of content for a new library's microsite.

Perhaps it'd be also possible to create a new archetype to simplify creation of a new microsite.