Lots of bug fixing and tweaking
- fixed LoginRequired having wrong link
- Curated optional fields in models and forms
- Add display of person having borrowed the media in detail view
- Don't save authors on media types which don't have the field
- Added a contact link
- Better game duration choices, games can have authors
- isbn both nullable and unique (forms need to coerce "" to None)
- is_present filter in advanced search
- Rework of return page
- More responsive borrow page
- Fixed mandatory tracks when editing disks
- Better home page content
- Better error messages
- Media are marked as present by default
- check of Med ownership replaced by a can_borrow field (the default behavior is still that only media owned by Med are marked as such)
Edited by nicomarg