Using publish middleware

This pull requests makes PeerLibrary use publish middleware. This is a way to stack arbitrary transformations between Meteor publish function and client, so that client can get some fields transformed/dynamic without them having to be stored in the database. Fields can also be per-user specific and so on.

This now allows that in every search results and publications lists around the site "full text" link is correctly displayed or hidden. Also filename under which user imported a file is now shown everywhere.