Half-title page should be wrapped in a div
Ticket #937
New feature: Inject House Styles
Changed images path to "assets", added ability to embed fonts.
Fix can't find fonts problem
Used sanitized basename as new filename.
Ability to insert MOBI house style
added to epub css's:  codes for: epub house style + mobi house style.
Improve our url() search/replace procedure.
Merge branch 'dev' of github.com:pressbooks/pressbooks into dev