Fix missing space in citation after comma.  

Relates to #2152 

@rbran100 can you review this?

Citations for book chapters and conference papers are missing a space after the comma when an editor is added to a publication.  Right now it reads In "book title","editor" - this places a space to it now cleanly reads In "book title", "editor".

Used this csl as a reference: https://github.com/citation-style-language/styles/blob/master/chicago-author-date.csl 

Update hook was needed because it appears the CSL files are stored in the DB and don't appear to automagically update when a csl file is changed, so we need to manually replace the file.